This 2000 song by indie rock band Grandaddy plays in the background while Rory and Tristan talk in the piano room, and eventually kiss. The song was a single from their album The Sophtware Slump, previously discussed, and went to #38 in the UK.
The Crystal Lake is about someone who leaves a small town full of hopes for the future, but is disillusioned by city life. In the same way, Rory thought that by getting out of Stars Hollow for the night she could run away from her problems, only to discover that the party in Hartford only brought her problems into sharper relief. The song makes specific reference to the emptiness of parties, and this one has left Rory feeling worse than ever.