Try these......silly I know, but pass away a few minutes. I do come across different things from time to time so wiill add more if you find these or other fun challenges amusing. :)
Get in practice for the summer months for this one..
http://www.majman.net/flyswatter/
With this one you have to click on the red square and keep it moving as long as possible avoiding touching blue or the black outer edge...
http://members.iinet.net.au/~pontipak/redsquare.html