10. Semisonic 'Closing Time'
Nineties radio was full of sentimental tunes about endings, maybe because the 20th century was coming to a close and everyone was feeling a bit of what Tricky called "pre-millennium tension." Semisonic's one huge hit was one of the best of this breed, and it endures as an alt-rock radio and karaoke bar staple. It would definitely be a great commencement tune, so long as you ignore that the song takes place at a bar around last call.