Oh my god. Soul sister! I adore Chris, and never more so than with JD! Unless we're talking Chris/Raphael. Or Chris/Raphael/JD. :) I've written a multi-part epic about those three. Not to mention one-offs of Chris/JD. (I've probably written a good percentage of what precious little there is out there.) And Chris/Ezra. Don't think I have any Chris/Buck, but that's because my Buck is usually also busy with JD. Or Ezra.
I'm quite fond of the occasional fic threesome myself.