There are a crapload of clubs here, and the Student Gov't gives each a fair amount of cash. It's pretty easy to start clubs, as well. Some of the most well-known, if not the most active clubs, are MOQA (Middlebury's GLBT and friends group), Riddim (A dance group that puts on a crazy performance twice a year), and any number of a capella groups that publish and sell CDs and tour to other schools.
Tons of options