1. You can buy one online from your favorite electronics site (but this will cost you an arm and a leg).
2. You can take your chances with a massager from the Goodwill Store (but who knows where that has been).
3. Or if you have five minutes to spare, you can build your own.
Not liking to spend great deals of money or break out in strange rashes, I prefer option number 3.
Step 1: Go get stuff.
- DC motor with a plastic gear attached to the shaft (easily found in tape players, VCRs, printers, etc.)
- An alligator clip
- Soldering iron
- Some solder