The topic says it all.  They can be depressing, they can be uplifting,
they can be emotionally wrenching.  But there's something about them
that makes your throat catch and your voice do odd things.

What do you go WAAAAAAAH! over?

My current choices:

The Bitter End
Hearts of Ice
Atonement
TIL #7
Chasing the Wind #7
Darling's Secret Date
the Patlabor fic that's not in front of me at the mo but was really good...
Likewise, Ken's Ranma fic that I can't remember the title of either...

           ^^^^^

        Ken who?

        Also, in addition to quite a few other fics not necessarily
on the above list, I'm inclined to agree with you on Hearts of Ice -
especially part 13, near the end when Masakazu passes away.  Krista
sure has a flair for that sort of thing.