I was thinking about a rating script, kind of like the one that imdb.com uses on its individual pages. A user can click a star on a scale of 1-10 stars, and it registers the vote, and also gives numerical output (such as 7.6 out of 10.0, etc).

For whatever reason, these are really, really hard to find on the net. I had a programmer attempt to make one for me, and it's very elementary, and allows for multiple votes...

Hence, it would sell