I am working on a project where I need to move the object from one point to another in a dead slow speed , The object doesnt weight more than 5 pounds .
I found a DC gear motor with has a RPM of 0.5 but I thinks its still very fast for my requirement . 
This is the motor :
<http://www.servocity.com/html/0_5_rpm_gear_motor.html>

This is the PWM :
<http://www.electronickits.com/kit/complete/motor/CKMX033.htm>

Please suggest a way where I can reduce the speed drastically (Either simply using a potentionmeter or any variable device) . motor needs to be small the rest doesnt matter .Or you can propose me a entirely new solution .