NEW YORK (MONEY Magazine) - From useless airplane miles to phone slamming to hidden hotel charges, there always seems to be someone trying to take advantage of you. Try these strategies to fight back.

Tim Winship, editor of FrequentFlier.com, says it's getting harder to turn miles into a seat on a plane going your way. Airlines may dangle an "unrestricted award," which gets you a ticket with fewer restrictions but costs twice as many miles. This is more expensive than it looks: Miles are usually worth about a penny each, so using even an extra 25,000 would run you $250.

How to fight back: Switch in Cleveland Winship recommends asking the airline to create an alternative itinerary -- perhaps making an extra connection through a less-busy airport -- that lets you use your miles. (Most airline Web sites aren't sophisticated enough for you to do this yourself, he says.)

Many airlines charge $10 to book through a real person, but that's a bargain compared with giving up twice as many miles. And they might even waive the fee if you ask nicely.

"Slamming," the phone scam that won't go away, is when your long-distance phone service is switched without your permission. It's illegal, potentially costly and hard to detect among all the inscrutable charges on today's bills.

How to fight back: Make a call By law, you don't have to pay for the first 30 days, so catch the slam early by scouring your bill regularly. Call the slammer -- the number will be on the bill, probably real small -- and demand that the charges be stricken.

Then call your real carrier and ask to be switched back for free. If things don't shake out in one billing cycle, take it to the FCC: 888-225-5322 or fcc.gov.cgb/complaints.html.

Ask your carrier to place a free "PIC freeze" on your account, preventing your service from being switched unless the company hears directly from you.

More and more little charges...from $20 resort fees to "discretionary" service fees (read: tips) -- are popping up on bills. What's up with that? Travel experts say that people tend just to look at basic room rates when deciding where to stay. Extra fees let hotels add to the bottom line while still looking like a good deal.

How to fight back: Scour the bill Ed Perkins, author of "Business Travel: When It's Your Money," says the front desk often can waive such charges. But consultant Bjorn Hanson of PricewaterhouseCoopers warns that hotels, which are looking to recoup renovation costs lately, have been taking a tougher line.

His strategy: Ask about extra charges up front, and note the agent's name. That will give you leverage if the bill at checkout says something different.