I do the paint can method too. Get a can, or a box, or what ever will just fit under the spinner, and lift the tail. repeat this 3 or 4 times. If the plane goes to one side every time, add some weight to the opposite wingtip.

Here's a little more info, scroll down to the part about lateral balancing:

http://www.rcuniverse.com/magazine/a...?article_id=84