It was driving me nuts too! Finally found it at http://www.azcentral.com/offbeat/articles/0507Friends-ON.html
It's "Embryonic Journey" from Jefferson Airplane's "Surrealistic Pillow" album.
> does anyone know the name of the song that played when the whole cast was walking down the hallway in the final scene on the friends finale? it sounds so familiar and it is driving me crazy!!!