I play a lot of cash games and a lot of tournaments and seem to do much better in tournaments. I guess I like  knowing that if I bust someone out of a tournament, they can't just go to the ATM and try and win back their money (assuming all the add-ons and re-buys are over). On the other hand, when playing in cash games the blinds don't normally go up so it's easier to sit at a table and wait for the fish to come in. 
I also find that my range of playable hands is much broader in cash games. Nothing changes statistically in cash games versus tournaments, but it seems easier to raise with a suited 8-9 in LP in a cash game than it does in a tournament game; I don't know why.
I just played in a No Limit Hold'em tournament tonight and managed to finish in the money. My last three consecutive hands were QQ, AK and AQ. The blinds were at $4000 and $8000 and the antes were at $1000. I was one of the shortstacks when I made it to the final table so I shoved with both my QQ and with my AK. I was in late position both times. Having picked up nearly $40000 with those two hands, never having to show any cards, I was content to min-raise my AQ (utg+4). The guy on my immediate left came over the top, all-in, and he had me covered by only $500. I felt like he thought I'd been stealing the previous two blinds and now I felt like he was just trying to buy the pot, so i called. He had AA