I have seen more complicated ones that couldn't do what this one will do.
The second project is a 1 page plan for a nice static balancer. My apologies I can't remember where I got it from, I found it printed off in one of my project binders. The plan is sized for balancing dirt bike wheels, so it may have come from one of the many motorcycle sites out there. It is sized for bike wheels, but of course you can balance anything that will fit inside the frame.
The plan is only one page but it is very complete, with full instructions. Dave Gingery built a smaller one in one of the Workshop Series books, but this is nicer and probably easier.