Health Tool Scripts

I am looking for some Health tools (Like BMI calculator, Calorie Counter, etc) for a health site I am developing. Does anyone have a source for these scripts?

There are plenty of "put this tool on your site", but I am looking for source code.

I realize they are probably pretty easy tools to write but it would help me out if their was a choice of already written ones.

You can PM me if you are interested in writing some for me (for a fee of course), although if I have to outline eveything I want it to do, I probably will just write them myself.

Any Sources?

Cheers