Many cyber-shoppers are learning the hard way that free online trials can actually cost a lot of money.

The Better Business Bureau recently included these "free" trials in their list of top 10 scams of 2009.

The credit card company Visa says 29 percent of their card holders have been victims.

"Most e-commerce merchants care about their customers and conduct business fairly, but even a few bad actors can cause consumer distrust," said William M. Sheedy, Group President, The Americas, Visa Inc.

"We want to let consumers know more about the protections they have against these types of practices and how to pursue a reversal of charges if they've been charged improperly," he said.

The Federal Trade Commission recommends before signing up for any free offers, consumers should make sure to read all the terms and conditions on their website.

The FTC advises consumers to pay special attention to any pre-checked boxes before submitting credit card information

Also, people should regularly check their credit card statements for any unauthorized charges.

*Originally published January 4, 2010.