JATE IS FATE! Seriously, Jaters, if you haven't checked out
sweetbelle07's awesome Jate mega post of DOOM, then what are you waiting for? :D
Let me also take this opportunity to recommend her fic
Twenty Random Facts about Jack and Kate. She's written a lot of great Jate fics, but this is just the best of the best (IMO).
Edited To Add: WTF Emily? Guess I really have missed a lot on ATWT...