Protobowl
Protobowl is a website created by Kevin Kwok which allows users to practice quizbowl questions, both alone and against other humans. Users may join a public or private room, and are provided with a random username consisting of a randomly generated adjective and noun, e.g. "exorbitant gull." Users may change their display names at any time, and can adjust the distribution or difficulty of questions that Protobowl displays. Protobowl is also available offline--which is probably a good thing, since it crashes with great frequency and gusto.