Gerbils- Wonderful pets. I've had them most of my life. They can be a little loud if keeping them in your bedroom (they love to dig and chew). They can be very tame, and easy to handle. They are also very easy to take care of. And as said, a pair can easily be kept in a ten gallon tank.
a little loud?
Mine kept me awake many nights with their noise. The digging, the chewing, the jumping up trying (and often managing) to get out, and the noisy wheel I had at the time *shudders*. Mine were in a plastic rodent cage which I really would not get a second time. As often as I had to patch that thing up because they had chewed their way right through it, glass fish tanks are definatly the way to go.