Super Smash Bros. Brawl. we visited the Dojo, N-europe, smash forums, gonintendo and countless other websites every single day until the release, it was the first time I've ever pre-ordered anything! and when we finally got it, me my sister and two of my bros played it every single time, so many times that I think we almost reached our melee play time!
we've been playing 4 player smash since the N64, meaning we were all very good, It got to a point where it became so competitive that a defeat would start an argument. but it didn't last long as we went straight on to the next match.
the rules were simple 3 stock, no time limit, no items, Final Destination... until KO do us part. We even made a rota for picking stages; 1st stage Final Destination, then Player 1's choice, then Final Destination again, next Player 2's and so on, in order to keep it fresh. the only games to ever beat our play time on brawl was; SSBM, Goldeneye 64, MK64 & MP 1,2,3 & 4.
when the Wii broke in January 2010, we didn't play smash until mid 2011. at school we had a smash tournament, I was pretty confident in my skills that I did not need to practice for it. I was right, I wiped the floor with them, even though they were pretty decent players. I went easy on them by taking easy hits and committing suicide while making it legit, but after a couple of matches I got bored and combo'ed them to death.
So yeah... Brawl = favourite Wii game ever.