Tag your iTunes tracks and create playlists from them.
A simple tagging app so you can add searchable tags to your tracks in iTunes. Now you can add relevant memories and points of interest to your tracks. You can use Twitagz to create playlists based on the tags a current track has (under 'Preferences' [command + ,]). SImply enter a word (or words) you want to seed the playlist with. Click 'Create a playlist'. TwiTagz will work for a second, create your playlist, and start playing it for you.