So I say Thank you for the Music, for giving it to me.

You're finally alone with a computer (hmmm... I think more about phone indulgences at some point) and you wish to hear a song you haven't heard for a long time, as you never have your CD's with you, or haven't bought one in years but haven't got around to an MP3 player. Have you tried Pandora.com? It's a free, yes free, music service. It even has an elegant way to get started as in you don't need to sign up for anything, simply type in the name of an artist or song and it get's going. It's sweet. And yes the service does remember songs from the seventies and eighties. You can listen and provide a thumbs up or down to help it learn the type of music you like.
A moment can be just searching your mind for a song from the past, typing it in, and then listen to it and remember the original moment of the life you were living when you heard the song, the hopes and dreams you had at that time.
And yes, they have Abba.
I've tried other services and will comment on them in a different post.