If you asked me to come up with a list of ways to destroy your credibility as an entrepreneur, here are two of the best ways I would come up with: associate with Mannatech (NASDAQ: MTEX), an embattled multi-level marketer, and associate with Robert Kiyosaki, the motivational author who has been exposed as a charlatan, exaggerator, and all-around bozo.

So it was with great amusement that I stumbled upon this press release:

Mannatech, Incorporated, a leading developer and provider of dietary supplements and skin care solutions, announced today its speaker line-up and events for MannaFest 2008. Keynote speakers include Bob Burg, co-author of The Go-Giver, and Robert Kiyosaki, author of Rich Dad, Poor Dad.

I've devoted a fair amount of bandwidth to trashing both of these. I first got interested in Mannatech when the Texas Attorney General sued the company for illegal sales and marketing practices. Then the company announced that its CEO was stepping down to -- get this -- devote more time to the company. Then, just when you thought this corporate outhouse couldn't get any goofier, Mannatech fired its independent auditor when the firm insisted that the chairman step down from his post.

And as for Kiyosaki: just read this blistering expose from John T. Reed.

Of course, it's possible that my impression of either of these entities could have been wrong. But Robert Kiyosaki speaking at Mannafest is the equivalent of Gary Condit and Mark Foley teaming up for a seminar on ethics.