Recently, we bought 10 coin like vibrating motors from Precision Microdrives. In the following video you will one of them in use. It is connected to an Arduino Uno micro controller.
Update:
Now we have built some wrist bands/straps using the vibrating motors, velcro, silver tape, arduino, batteries and more.
Hopefully, we will have a couple of interesting research projects that make use of them in a near future (currently we have two planned). Right now the plan is to use PsychoPy to control them for our experiments. In fact, we have one planned to start in two weeks and another for being piloted this week. One more applied cognitive psychology/human factors and the other project more ground research. Very exiting. I may update the blog with a new post when we tested more.