Are there any good ones? I've been replaying Kotor II this past week and I'm in the mood for some fanfiction.
Some quick searches at ff.net turned up at best, mediocre stuff.

Revan as protagonist not required.
HP crossovers welcome.

I've read The Havoc Side of The Force [excellent, check it out if you haven't yet] and an older 100k word one in which Harry was Revan and came back to earth with Bastilla [can't remember author or title but it sucked].

HK-47 always a plus.

 

This is a bit of an odd one, but still very good. Well written, interesting ideas, good length. I highly recommend it.

 

That's "Harry Potter and the Dying Embers".

I didn't mind the purely Star Wars portion at the start, but then I hadn't read any other Revan stories so I didn't have much to compare it with.

 

I remember liking Revanchism, though it hasn't been updated in a while. It's an AU about Revan fighting in the Mandalorian Wars, with a talented young Bastila Shan being assigned to him as an apprentice. It's a romance, but it does a good job of showing the war from what I remember and the relationship between Bastila and Revan is fairly interesting.

 

I remember enjoying Revan's Rotten Holiday. And just so you know, it is a humor fic. Still, from what I can recall, it has decent characterization and some pretty good moments.

 

The Gathering Storm and its sequels by rogermein come to mind. These fics are focused on a couple of solo missions Revan did pre-kotor. The text can be quite mediocre at times but I remember very much liking the stories.

I do have to give a warning. Unlike what ff.net conveys I would rather describe it as a horror, especially the last sequel. The gore can be quite graphic despite the T rating.

 

Conduit was a really good Mass Effect/KOTOR xover with Revan appearing in the Mass Effect verse. Hasn't been updated since 2011 though. That said, it was a great read.

 

It's an interesting read, as the plot is well thought out and meshes more or less with canon. But holy shit his Revan never uses the force. This is what disturbed me the most, one of the most powerful force user in all time only uses his light saber. Now I quite like that the author wanted to show us a Revan who only relies on his wits, but he isn't even that smart.