The Best of All Possible Worlds: NC-17. Jeanita Danzik. Q takes Picard to the Mirror Universe (the one from Diane Duane's Dark Mirror where the Empire still reigns, not the one from DS9 where the humans have been enslaved), where Picard becomes obsessed with helping his counterpart develop a sense of morality. Contains rape and torture (mostly Mirror Picard on Mirror Troi), and consensual slash. P/Q, P/Mirror!P, Mirror!P/Q.
In the Valley of the Shadow: NC-17. Jeanita Danzik. Sequel to "Best of All Possible Worlds". Mirror Picard has become Emperor with Q's assistance. While Q is investigating why the Mirror Universe is so dark, Mirror Picard discovers that Q has continued to have a relationship with the regular Picard, and feels betrayed. M/M sex. P/Q, P/Mirror!P, Mirror!P/Q, P/OFC.
Q-Struck: PG-13. Atara Stein. P&Q friendship with Q wanting but being okay with never actually getting more than that. The Continuum force Q to test Picard by giving him Q powers, and Picard goes insane. After subduing Picard and getting the Continuum to promise no more tests, Q insists on staying aboard the Enterprise to supervise Picard and help him recover. Atara's one major flaw in P/Q fics, in my opinion, is that the characters are both too insightful about themselves and their own motives, and too willing to admit it to each other. But with that caveat this is a good friendship/unrequited love fic. She Moves In Mysterious Ways: NC-17. Atara Stein. Genderswap with fem!Q. After "Generations", the loss of his ship makes Picard feel somewhat reckless, so when he meets a mysterious woman teaching at the Academy, he enters an affair with her despite the fact that he does, in fact, know exactly who she really is. There are two sequels but I liked this one best. His Beloved Pet: NC-17. Atara Stein and Ruth Gifford. On a bet, Q seduces Picard. They both get more than they bargained for. This is hardcore BDSM with dom!Q/sub!Picard, which isn't to my taste, but the authors do a good job of explaining what someone might get out of such a relationship, and the meat of the story deals with love and betrayal anyway.My Fair Jeanne: NC-17. Ruth Gifford. Most genderswaps change Q; this was the first one ever to swap Picard. Picard wakes up female one morning. He's convinced Q is responsible, but Q is refusing to show up and take credit... until the most embarrassing possible moment. Fem!P/Q, P/Q, P/Fem!Q, Fem!P/Fem!Q. A little heavy on the power games, with Picard as sub, but no S&M.
Love Reign O'Er Me: NC-17. Ruth Gifford and Varoneeka. NC-17. Avoids the worst excesses of both writers, neither too soppy nor too obsessed with power games. After Q kidnaps Picard to a world he created, the rest of the Continuum gang up on him and dump him, with complete amnesia, on the same world. Q is OOC, but deliberately so; the authors are going with the apparent assumption that Q is as big an ass as he is after millions of years in the Continuum, and perhaps at the dawn of time he was much more open and a nicer person.
An Hour of Eternity: NC-17. Varoneeka. I have a serious problem with Varoneeka's fics; firstly, once she gets to the sex in any of her fics, the characters go seriously OOC, with many overdramatic declarations of love, and secondly, her interest in literally eternal love, soul-bonding, dying without your love, etc... doesn't actually seem to fit this particular pair at all. But that may be because I don't find that trope appealing. I recommend this story anyway, even though, like all her fics, it goes pear-shaped in my eyes once the sex starts, because it's the story with the longest buildup and getting-to-know-you period, and she writes that part very, very well. Picard is transported through a rift to another dimension's 20th century Earth, and Q follows him to rescue him... and is then cut off from the Continuum and loses access to his powers. The two have to survive in New Orleans with no money and no resources other than Picard's Starfleet skills and Q's intelligence.Le Q Entre Deux Chaises: PG-13. Ariana. Q's mate comes to see Picard to confirm whether Q is cheating on her or not, Q shows up, and somehow Q ends up powerless for a single night in Picard's bedroom. This is probably the only decent "Q's mate is jealous" fic I've ever read.
Open Sesa-Q: PG. Mercutio. After Picard's assimilation, Q comes to offer him three wishes. This is P&Q rather than P/Q. Picnic A La Q: PG. Mercutio. A cozy domestic scene between Picard and Q is interrupted by Q admitting to himself that it's never going to happen. Kind of funny. Raison D'Q: PG. Mercutio. Unrequited love on Q's part. Q comes to Picard, haunted by the knowledge that he has learned what he was made for, cannot help but do what he was destined to do, and yet his feelings for Picard make him want not to do it. C'Est La Q: PG. Mercutio. Sequel to Raison D'Q. From Me To Q: PG. Julia Houston. Can be seen as P&Q or P/Q unrequited. Reads like it actually could have been an episode of the series. On a mission to a world consumed with apocalyptic fear of Cleansing, the Enterprise crew run into Q, who's there on his own agenda, and a mysterious woman who turns out to not actually be an OC at all. Q Music: PG. Julia Houston. This one makes the P/Q pretty explicit, but no romantic relationship actually starts. Introduces an OC who would break every Mary Sue litmus test except that the author's skill is enough to keep her from becoming a Sue. Political intrigue requires the Enterprise crew to try to recruit an alcoholic practitioner of a deadly alien musical art to help them impress warring alien races, but the singer has some sort of connection to Q. Past Duties: PG. Shalott. Picard is old, retired, and bored. Q comes for a final visit. Accidental: PG. Shalott. Why it's not a good idea to surprise omnipotent beings. Sanity: PG-13. Tiggy Malvern. Picard wants Q and he knows Q knows he does, but it's not that simple. This one's all UST, and has much, much better reasons for keeping Picard away from Q than "he doesn't know he's attracted to Q", and the combination of a Picard who knows what he wants and still feels his duty doesn't allow him to indulge what he wants is more in character than most other Picards in P/Q fic I've encountered. Reality: NC-17. Tiggy Malvern. Sequel to "Sanity." Hard Won: NC-17. Nick. (sadly, permanently incomplete) The Picard and Q in this story manage to snark at each other and engage in witty banter *while* having hot sex that demonstrates genuine affection, which is approximately ten zillion times hotter than stories where the sex makes them go completely soppy and OOC. This was a linked series of stories. Unfortunately the author apparently decided to stop and has marked the series as permanently unfinished, after leaving off at a heartbreaking cliffhanger. A Thousand Years: PG-13. JM. A songfic, but the song's actually appropriate. P/Q unrequited. Q is haunted by what his feelings for Picard have made him. What Lies Within: NC-17. JM. Picard/Guinan, Picard/Q. Guinan makes the mistake of using her dearest friend's love for her as a weapon against her most hated enemy. Everyone ends up hurt. Carnal Pleasures: PG, despite the title. Andraste. Deja Q spinoff. Some time after losing his powers, Q comes to Picard with a proposition. Picard doesn't quite know how he feels about that. THEM: PG. Vic Taylor. P/Q implied. What Q was thinking when he almost answered Picard's question at the end of "All Good Things". InQsitiveness: PG. HalfshellVenus. Picard was trying to have a peaceful vacation on Risa with a lady friend, until Q showed up, jealous. Manners Are For Mortals: PG-13. HalfshellVenus. Q shows up and bugs Picard while he's in his underwear. Pretty funny. The Indomitable Picard: PG-13. Jedi Buttercup. Established relationship P/Q. Picard gets into an argument with Q because Q has been mucking around with the timeline. Explains "Enterprise" as well as anything else. :-) Home: PG. Ironical Jester. Picard is dying, refuses a cure, and has agreed to let Q take him on adventures in the last year of his life. Q is not sure why he is putting up with this. Sardonic and touching at the same time. One Thousand Eyes: PG-13. Necromania. Q watches Picard as he sleeps. QP: PG-13. Entipy of Nothing. Q is obsessed with Picard and hates what he has become from it. A Far Distant Star: PG. Icarus Chained. While teaching Troi to shield better, Q accidentally lets her see something in his mind that almost destroys her. He turns to Picard to help her because Picard's the only one he's willing to admit the knowledge that harmed Troi to. Maybe a bit over the top and overemotional, but the concept is original and the story's well written. Human: PG. Icarus Chained. Established relationship P/Q in which Q finally explains to Picard exactly what was so bad about being human. Thank You: PG. Icarus Chained. What the expression "thank you" means to Q. Infatuation: R. Sasha Anu. Picard figures something out about Q. Q does not like what Picard does with the information. Kind of a dark, nasty Picard but in a way that's not unbelievable. Repression: NC-17. Maraceles. They're both slightly horrified at what they're doing, but that doesn't stop them. Probably one of the most realistic Picard/Q sexual encounters ever written in my opinion.