Has anyone heard of the supplement berberine? Supposedly it is good for regulating blood sugar and a bunch of other things. I believe they're even looking into it as an anti cancer agent.

Here are some studies on it:

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2410097/

http://www.naturalmedicinejournal.com/article_content.asp?edition=1&section=3&article=387

http://www.naturalmedicinejournal.com/article_content.asp?article=384