Well, I wouldn't perform just a colour change, but that aside, favourite colour changes... The Passover Change... Alain Nu's Winter Change variation... And can't go past a good Erdnase Change - I use the technique found in Jon Racherbaumer's Card Finesse II, except just for a single change (I'd credit it more precisely, but my ex-girlfriend has the book, and I don't particularly feel like contacting her! ).
-Erdnase (180 degrees)
-Shapeshifter (180 degrees)
-Winter Change (great angles if you have a large palm, if not about 120 degrees)
-Cardini or Ego change (90 degrees)
My favorite at the moment is the winter change because it looks so magical
Erdnase, Top change (yeah, it's not 'visual' but it works), I find myself doing the Ego change with small audiences, Winter change is great (though these spirit fingers sound like they'd double the impact...)
Just a few
The clipshift is pretty amazing in the right hands, not my cup of tea though.
i do a version of the Ego change, where i slowly wave my hand over it and it changes, also a fantastic vanish, and I've done it 360 degrees surrounded with no flash
it's slow and pretty visual, you see the card on one side of my hand, as i wave it slowly across you can see it vanish as my hand is going across