How e-ripoff artists work (and how to avoid it)

Cancer is an insidious disease. Hidden, it can spread with frightening speed until it is out of control and unstoppable. Early detection helps. But you have to know what to look for.

Likewise, the Web has a growing cancer: Online fraud. The National Fraud Center says online fraud is growing exponentially. Click for more. Just yesterday, the FBI said the proliferation of computers has made life all the easier for criminals. Click for more.

Here's what crooks are up to online and the early-detection tools you need to stay safe:

AUCTION RIPOFFS
The Federal Trade Commission reports a 20-fold increase in complaints about online auction fraud over the past year. Most involve non-delivery of goods. Click for more. It's gotten so bad some Netizens formed a cyber-posse to catch a con man. Click for more.

INVESTMENT SCAMS
Investors looking for quick riches are easy targets online. State securities regulators say dangerous deals include: Small stocks with inflated values, bogus offshore "prime bank" notes and pyramid schemes. Click for more.

BOGUS EMAIL
Your email is another area where crooks love to sucker you. Watch out if you're asked to email your credit card number to fix a 'billing' problem. Click for more.

SHODDY DEALS
Be wary of companies that fail to deliver, especially on low-cost or bare-bones products. PC maker Microworkz.com is accused of violating consumer-protection laws related to computer equipment that was never shipped. Click for more.

PREVENTION TOOLS
Take these tips from ScamBusters to avoid bogus online items:

Don't buy if you hear about it via spam
Always use a credit card to make your purchase
Buy at reputable auction sites, and only from sellers with good references
Don't conduct business with an anonymous user
Be cautious if the seller uses a free email service
Save copies of all emails and other documents involved in the deal
Trust your common sense and intuition

Follow these five tips for safe shopping, as outlined by the National Fraud Information Center:

Know a site's privacy policies; reputable ones clearly state them
Look for plenty of information about the offer; good vendors provide lots of important detail
Check out the seller; a physical address and phone number could be vital after the sale
Know the delivery date of the product or service
Expect security; quality sites tell you how they protect your financial data

Doctors have yet to wipe out cancer. Online fraud won't be wiped out any time soon either -- if ever. But if you know what to watch for, you can detect it before it has time to damage you or your family.

What online frauds have you encountered? How did you fight back? Tell us about it at editor@zdnetasia.com.