cmelbye, you are right to point this out - there are actually several incarnations of free find in page bookmarklets floating around the Web since 2007. I even wrote this post explaining why I felt the need to create my own and charge for it:

http://findinpage.blogspot.com/2010/01/what-makes-this-find-...

In a gist, all the ones I have tried have no UI and have major design and usability, not to mention technical issues (you can read the blog post for details). At any rate, they were not good enough for my own use.

The idea is that if you have a serious need for a reliable, convenient, usable tool then you wouldn't mind paying $0.99 for it.

Cool. I will have to try this out too!