There are many songs already mentioned that make me cry, but here are a few that may have not been mentioned yet...
Acoustic version of "Everlong," Foo Fighters
"Time to Say Goodbye," Sarah Brightman/Andrea Bocceli (sp)
That song off the latest Avril Lavigne CD about her grandfather passing away... "I Miss You"??
"You Know You're Right," Nirvana
"Long December," Counting Crows ("it's all alot of oysters, but no pearls")
"In This Diary", The Ataris and "One Hundred Years", Five for Fighting, both about growing older
"Scarlet Ribbons," Harry Belafonte
"Dreaming My Dreams With You," Cowboy Junkies
"She's Leaving Home," Beatles
"Forgive Me," ?? bonus track, Alanis Morrisette Jagged Little Pill