Three is hard to do when you have a lifetime you're covering.. I don't recall actually ceasing to like any bands, unless you count Metallica's "eyelashes and furcoats" stage.. I still like their old stuff, and actually liked St. Anger
I like non-mainstream stuff too..
Yeti
Strapping Young Lad
Circle of Dust
Frontline Assembly
But ever since my car's tape player/CD player died (about two years ago).. I rarely get to listen to anything anymore.. and I miss it.
Opeth
Dragonlord
Iniquity
Dimmu Borgir
Old Man's Child
Naglfar
Borknagar
Chthonic
Behemoth
Children of Bodom
cKy
Lamb Of God (Ashes of the Wake & As the Palaces Burn)
Dethklok
Mushroomhead (old stuff, XX & XIII)
Queen (lol)