My favorite pokemon is Carracosta. I like his sprite, his defense, his ability in solid rock, and the fact that nobody in OU tiers knows how to handle it when I sweep. He has access to shell smash, which enables him to be either a physical or special sweeper, with access to stone edge/rock slide, waterfall/aqua jet, and Earthquake, as well as Ice beam, scald, hydro pump, Hidden power fire. Solid rock enables him to tank like crazy against physical attacks, and gives him a chance against special attackers in sand.
Really, the only thing I don't like about Carracosta is his 4x weakness to grass.