great songs listed here
Wilco - I'm The Man Who Loves You, Walkin'
U2 - Beautiful Day, Veritgo, Window in the Skies, Original of the Species, EBTTRT, Discotheque, Streets, etc... a lot of U2 songs make me happy
Alien Ant Farm - Glow
Red Hot Chili Peppers - By the Way, Can't Stop
Weezer - Island in the Sun
Bloc Party - Banquet, Hunting for Witches, Waiting for the 7.18, I Still Remember
Bright Eyes - Bowl of Oranges (whenever I wake up with this song stuck in my head I know it will be a good day)
The Beatles - Drive My Car
Arcade Fire - No Cars Go, Wake Up (because I expect U2 to come out
)
there are many more. I know, I'm totally ignoring the 5 rule. I'm awesome like that.