I'd like to create a tiny (1 inch) wireless ball or rectangle which could vibrate.
I was wondering if Arduino could be used for such a project, I've tried to find some actuators that I could use without any success, your help would be greatly appreciated.
Try using the vibrating motor from a mobile [cell] phone. If you've got an old one, disassemble it and take the motor out. They're tiny and would easily fit in your ball/cube. They run on about 3 -4 V (3.3 V??). I've got one running on 3 NiCads ( 3 * 1.2 V = 3.6 V) quite happily. I don't know how much current they draw, but it's fairly minimal. Use a 2N2222 to control it from your Arduino.