Most travelers know that the mini-bar is nothing but a fee trap. But a $6 Snickers bar is a sweet deal compared with a $30 resort fee. The hotel industry raked in $1.6 billion in fees in 2006, according to PricewaterhouseCoopers.

Yet predicting what you'll pay can be hard because chains often don't have an across-the-board fee policy. "You could be in the same city, in a different hotel of the same brand, and still pay different fees," says Bjorn Hanson of PricewaterhouseCoopers.

Your best defense? Ask about extra charges before you book. You'll have the most leverage before you promise a hotel your business. Among the biggest outrages in PricewaterhouseCoopers' latest survey:

8. Internet connection fee $9.95 a day. Mid-price hotels tend to offer free Net access to lure business travelers. High-end hotels are more likely to levy this one.

9. Resort fee $10 to $30. You might be charged this even if you never dip a toe in the pool or break a sweat on the treadmill.

10. Automatic gratuities Just in case you neglect to tip the bellboy or maid

11. Package delivery fees $5 for the hotel to accept a FedEx package for you

12. Mini-bar restocking $10 on top of what you pay for the junk food and liquor