A few months ago, one of my coworkers bought this stuff called Crazy Aaron’s Thinking Putty. it an industrialized version of SillyPutty, and it’s great for strengthening your hands, or just working out frustration. I bought 3 cans of the stuff. Two for at home, and one for the office. You can get it at http://puttyworld.comI highly recommend it, and had no shipping issues. I use it every day, sometimes for hours.