Originally Posted by Kukuk 
Man, there's nothing more satisfying on SWTOR than undercutting people in the Galactic Marketplace. Logged in today to see all my stuff had sold, netting me a cool 90k. 
I don't recall credits doing anything useful in the game, they're only for repair bills and consumables. Making gold in GW2 was immensely enjoyable, as the currency actually had worth, and it was difficult to farm.
When I was playing SWTOR, healing people in the battlegrounds was pretty satisfying, there weren't many healers around at launch, and the few that were around, were terrible.