This is an excellent way to lose all your money AND (if you’re unlucky) go to jail at the same time. 2 for 1 deal, here’s how it works:

1. You cash a check (bank has to, by law, give you access to the funds within 5 business days, regardless of how long it takes them to actually get the money)
2. You remove the cash from your account (that’s what a money order is, the cash is GONE from your account and is now in a custodial account).
3. The check bounces. The money is removed from your account and you are responsible as a willing conspirator in the fraud.

http://en.wikipedia.org/wiki/Advance_fee_fraud#Fake_checks_and_check_cashing_scams

See also:

http://en.wikipedia.org/wiki/Check_fraud

Here’s a typical sob story, with luck you could get your 15 minutes of fame too, apply now!!

http://www.washingtonpost.com/wp-dyn/content/article/2006/05/31/AR2006053102004.html

Your exact “opportunity” is on page 2:

In February, about a year after Gaston had posted her résumé on a job-search Web site, she received an e-mail about a part-time opportunity: to work as a courier for money for an international charity that builds homes for people in disaster areas. Her assignment was to deposit local donations into her own bank account, wait for the checks to clear and then wire the money to another address. She was told she would be paid 7 percent of every donation check, with a guarantee of $500 the first week on the job.