There are lots of free interval drillers out there that you can find by Googling around. I think this one has a few features which make it desirable:
Download IntervalBlaster.zip [552K]
Upzip all of the files to a single directory. Click on intblaster.exe to start. You should even be able to do this on a lab computer, friends computer etc. without screwing anything up -- just delete the whole directory when you are done!
This version was posted 3/19/2005. As always, feel free to email me with comments, questions, or suggestions.