Any pieces that just make you grin when playing because they sound so powerful/impressive?
I like Rach's prelude in G minor more and more each time I hear it; how it builds and builds, then falls, and builds up again. I love the way that D chord sounds, setting up those rapid half steps that eventually tumble down into the original theme for another onslaught.
This piece is going to soon take priority on my "to learn" list.