ZiT
ZiT is a music identification system available though your (in game) mobile phone. This system allows players to be to identify any song by dialing ZIT-555-0100 where an automated Message from Lazlow will ask you to let him hear the song. You will then receive a text message providing the name of the song and the artist. If signed up to Rockstar Games Social Club you'll also receive a (real) e-mail titled New Song From ZiT at Rockstar Games Social Club with the name of the song, artist, give you a link to itunes and will save the song in a ZiT Player to give you a preview.