On last.fm, I like to make playlists of songs I want to preserve with a certain moment in time. Like, I just had an incredible experience with Dark Matter by PT, so I just added it to my 2010 playlist. I separate the playlists by year. And I put them in chronological order... songs from January would be at the beginning, some in December would be at the end of the list.
Anyone else do stuff like this? Liike make mix tapes that relate to great memories?