At Cool Tools, Jeff Bragg reviewed the Roland MicroCube, a nifty small amp that has digital modeling to emulate the sounds of different classic, larger, amplifiers. On Amazon, it can be found for as little as $(removed)
This little amp has been around for about four years and is loaded with features closely related to its larger, louder cousins. The controls on the top provide a wide range of sonic possibilities. Along with a knob for tone, there are controls for gain (think distortion control) and volume. Most importantly, the MicroCube uses digital modeling to make it versatile and good sounding. What's digital modeling? That's where you take a bunch of great-sounding full-size amps and digitally sample the sounds they make and then apply that to the sound architecture of another amp.