Jeez, putting together a recs post is so much more work that I had anticipated. This list covers my own favorite Ichigo/Rukia fic pretty well, but it is by no means exhaustive. If there's something you think is missing, please, share it in the comments. And if you have reservations about any of the fic on here, feel free to explain why, too. We want this comm to be criticism-friendly. Keep us all on our toes.
So, in no particular order, these are the Ichigo/Rukia fics that make me proud of the fandom:
Holes in the Rain -- One of the many insomnia fics that ichiruki lends itself to, or did in the days when the couple was sharing a room. Nice, not overdone, some lovely images... plus, subtle mommy angst.
A Christmas Parallel -- Has the problem all Christmas fics have, which is that Rukia wasn't in the human world during the winter (although now it's fall in canon, so I guess if she sticks around one could assume these fics are post-Soul Society arc), but Ichigo and Rukia are wonderfully snarky and yet adorable.
4:00 AM -- More insomnia fic. This one has a neat twist, though. And I wish the author would write a sequel with the awkward hijinks that have GOT to occur the next morning! But that might just be because I enjoy Ichigo being freaked out a little too much.
I Want to Save You -- Ichigo training during the Soul Society arc and remembering one of those little unimportant moments from when Rukia was in the human world. I love fic where she doesn't understand human things (the Anya Factor) and this is one of those.
Waiting for Shambala -- One of the few realistic Rukia-goes-the-human-world-to-stay post-Soul Society fics I've read. It actually deals with a plausible (and therefore, kind of depressing) reason for her to return and stay, and the consequences of living in the human world that aren't all fun shippy hijinks. Rukia in this fic reminds me very much of Anya in "Selfless." This is a very good thing.
Excessive Chain -- Pretty much the only other Rukia-stays-in-the-human-world post-Soul Society story I know of that deals with the issues realistically. Even more depressing than Waiting for Shambala, but in a good way. It hurts and you want more.
Razors -- Short first-kiss fic featuring superior-in-her-ignorance-of-human-ways Rukia and a very embarrassed Ichigo. Just the way it should be.
Rabbit Food -- The only fic combining Rukia and bunnies I've been able to stand, for good reason. Rukia is a very practical person.
Sitting in a Tree -- My favorite of "The Other Side of Ordinary" 'verse, one of those futures where Rukia's living in the human world and openly in a relationship with Ichigo... only good. Full of snark and crazy Rukia-logic, plus plenty of the rest of the Kurosaki clan. I'm always uneasy with the concept of Rukia just up and staying in the human world, but this is one fic I'm willing to overlook that for.
Imitation of Life -- Another one where Rukia stays in the human world; not as lighthearted as Sitting in a Tree, but not as melancholy as Waiting for Shambala or Excessive Chain, either. Done in a contemplative style that feels a little like a fairy tale retelling.
Like Hamlet -- There is just not enough fic that makes use of Ichigo's love of Shakespeare. Seriously.
Keep Reading -- 100 word drabble, featuring more lit geek!Ichigo. Not Shakespeare this time, but still so very right.
Human -- Nice, awkward first-time sex. Uh, but not porny. Occurs really early in the series, which kind of makes the mind boggle if you think about it too hard, but it makes sense when you read it.
A Debt Unpaid -- post-213, Ichigo makes Rukia promise to kill him. It's kind of amazing how neatly this (the fic, not my lame summary) captures their dynamic.
Butterfly of Death -- One of the first non-sucky Ichigo/Rukia fics I ever read. It's very short, and angsty, but somehow the pretty hits me harder than the angst. [Warning: link goes to the Pit of Voles]
Personal Buddha -- Normally I find Berry's fic a little too romantic to fit my images of Ichigo and Rukia, but this one is from Hanatarou's perspective, so it makes sense that they'd be a little off. And I'm a whore for the kind of fic that looks at the main story/heroes from the perspective of minor characters. [another ff.net link]
Proposition -- I think Celeste is generally overrated in this fandom, but I can't resist reccing this one fic. In which Ichigo proposes marriage. SHUT UP. I swear it isn't sappy. The narration has some spontaneously shifting POV issues and a couple of sentences I have to edit in my head to be able to read, but the dialogue is awkward and snarky and right and there's kicking and I love the ending. [this is my last link to that hellhole, I swear]
Ten's "Eyes" series is practically epic now; it features some yummy, fucked-up, well-developed Anti-Ichi and his wonderfully twisted interactions with Rukia and then with Ichigo as well. The imagery inside Ichigo's head is lovely and amusing and causes some very complicated fallout that forces more that a few characters to deal with some issues they've been avoiding, and it all builds up to the only really earned, in-character, fittingly awkward first-time smut I've read for this pairing. There are at least a couple more stories in this 'verse to come, but here are the stories so far:
1. Eyes Turned Inside Out
2. Eyes Closed
3. Close Your Eyes, Maybe He Won't See It
4. I Can See with My Eyes Shut
5. Eyes Turned Inside Out (Punchdown Mix)
6. Eyes Open
The Girl on the Bridge -- That girl, not that bridge. Alternate Soul Society reunion, very short and a wonderful combination of grumpy Ichigo-brain and lovely imagery.
Scholars and Gentlemen -- Ichigo Vs. Byakuya, lit geek deathmatch. So beyond brilliant. The things Ichigo goes through for Rukia...
Bunny Prints -- All the use Rukia has for textbooks. Crappy art, snarky dialogue, friendship and the word "cantankerous." Awesome.
Heavy Breathing -- Ichigo takes Rukia jogging. People notice her fine, fine legs. Not enough fic (outside of sappy crap) gives Rukia the credit she deserves for her hotness. And Ichigo is wonderfully underhanded about helping her.
Eree has about a million and a half drabbles that are all awesome; these are a few of my favorites.
Too Proud to Tell You -- Rukia near the end of the (first) Memories in the Rain arc. Short and smart.
VCR, TV, and Other Such Confusing Acronymns -- I think by now we all know how I feel about fic that features Rukia encountering new things in the human world and applying her own logic to them. Ichigo getting all frustrated is just a bonus.
Strange, This World -- Yet another ficlet about Rukia and strange human stuff, but this one manages to take what could be a simply wacky scenario and make it a really poignant depiction of Rukia's alienation. So well done.
Contradiction in Terms -- Just. I love this one. It's so simple and so packed with meaning, in the way Rukia is conflicted and the way Ichigo tries to handle it and yes.
Can You Hear Me Now? -- Before we found out what Ukitake gave Ichigo in 181, everyone speculated it was a cell phone. Eree followed this to its logical conclusion. Fucking awesome crack.
(I am not above reccing myself but I did ask my co-mod to write the little blurb-things for me, so I take no responsibility for any false advertising here. Complain to Eree.)
Mistletoeing -- A suckerpunch of awesome to all the people who insist on writing schmoopy Christmasfic. I can see Rukia doing this in canon, too.
The Hunt for Tact in its Natural Habitat -- This fic takes two concepts that could go horribly wrong (Rukia in the human world and menstruation) and turns them into a complete riot. Orihime's characterisation will end up destroying your perceptions of your period forever. Also, bonus Karin and Yuzu!
In the Name of the Moon -- I love this: backstory to just how Rukia got up on the windowsill in 195. It even ties in to Rukia's obsession with shoujo manga. A great story with snarly!Ichigo and Rukia banter, which I'm always a sucker for.
Someone Who Outdrew You and Not a Victory March (co-written with tenebris) -- Orihime fic and Ichigo/Rukia that remains squeeable without veering into OOC territory. This is the side of 213 we don't get to see. If your heart doesn't break for Orihime here, well, you don't have one.
Aaaaaand I'm spent.
PS -- I updated the first community post with some guidelines, so if you're thinking about posting something here but aren't sure what belongs, have a look.