Gear Motor 10 - Geared pager motor
81:1, 454RPM, 20mA (220mA stall) at 6V gives 3.17in*oz torque.
These little gear motors measure 20.8 x 29.0 x 25.4mm (0.82 x 1.14 x 1.00") and weigh in at 4.7g (0.17oz). The square output shaft measures 3.56mm (0.14") per side, and the leads measure 5cm (1.95") long.
They're a bit funky in that they're not continuous rotation by default. They have a self-centering spring, so applying DC power will result in a 60 degree swing in one direction. Reversing power swings the output arm 60 degrees the other way. Remove the self-centering spring and clip the stops, and away you go!
This last picture is of our micro-sumo robot (5cm cube limit), and it is QUICK on a 7.4V LiPoly battery. These wheels and motors are a great combination!
[Data Sheet]: Solarbotics Gearmotors Specification Summary
[Data Sheet]: GM10 Dimension Specifications
[Data Sheet]: GM10 Performance Datasheet PDF (151KB)