Great...Well, I'll look at it again and see what's wrong now. At least it's not crashing your browser like it did to me for a while...
EDIT: Well, I've reworked the randomness of it so at least now you've got an equal chance at seeing any given fiver, but I don't know why you would be seeing the same one over and over. If it still doesn't work, I've got another page that won't redirect you immediately and should be suitable for bookmarking the normal way.
http://www.webpages.ttu.edu/jonray/rfiver/index.html