BusinessWeek: Five timeless business scams

The following are scams that are circulating by email, regular mail, or phone calls that everyone should be aware of:
Article: Would I lie to you? Five cons still kicking
http://www.msnbc.msn.com/id/12394486/
http://www.msnbc.msn.com/id/12394486/page/2/
They've been around for generations, but people still fall for them
1. The Scam: Free Money -- Charismatic individuals claim they know of funding sources that don't have to be repaid.
2. The Scam: Patent and Invention Services -- Business "experts" evaluate your invention or business idea, declare it a sure-fire winner, and ask for thousands of dollars to secure intellectual property protection, help you find manufacturers, and do marketing.
3. The Scam: Advance Fee Loans -- Companies promise loans to would-be entrepreneurs who cannot get capital from banks or investors.
4. The Scam: Work From Home -- It's only after you've made an investment that you find out the business isn't so easy.
5. The Scam: Wealth-Building Seminars -- Few people actually get richer, but many people get poorer attending these meetings, which are often held at hotels near airports.