Does your credit card give you something back every time the cash register rings? More than half of cards issued have a rewards component -- typically worth $0.01 to $0.03 per dollar spent -- and the goodies range from free Frappuccinos to contributions to Junior's college fund.

Perks aplenty; gotchas a-go-go
Airline miles are so yesterday. To make their perks look richer, today's rewards programs offer chits with retailers, environmental groups, resorts, and even discount brokerages and college savings plans. And then there's cash back. Payouts of up to 5% are becoming standard fare. (Note the "up to" verbiage.)

New customers are wooed as fiercely as pro athletes are -- signing bonuses and all. You can often get enough points for some valuable stuff just by applying. But even though finding a loyalty program that suits you isn't difficult, cashing in on it -- well, that's another story.

According to Consumer Reports, 75% of airline miles go unused every year. It's no wonder, given the plentiful and ever-changing rewards-card restrictions. Popular frequent-flier programs have instituted tighter expiration guidelines for unused miles. Many programs render points worthless within a year or two and even start the use-it-or-lose-it stopwatch retroactively.

It's not just credit card companies watching the clock: Airlines are also forcing people to forfeit miles if enough time goes by without any activity. Often, you can revive expired miles, but at a cost -- fees that are sometimes so high, it doesn't make sense to pay them.

Nevertheless, don't give up entirely on the free-lunch promise of loyalty cards. Just recognize that going from frequent buyer to frequent flier requires some detailed planning -- and some discipline.

Tips from a pro
For tips on turning points into magnificent trips, I went straight to my personal travel guru -- a fellow Fool who in three years has taken $35,000 in free trips. She and her husband have traveled to Africa (three times), India, and China without paying a dime. Her secrets: flexibility and persistence.

She consolidates points with Starwood Hotels (and its dozens of airline and hotel partners), plans six months before departure or snags last-minute deals, and doggedly calls to cash in. More of her tips:

Concentrate to accumulate. Don't limit your point potential by spreading spending across multiple cards. And sign up for all major airlines' frequent-flier programs. They're free, and they come with member-only alerts.

Look for alliances. Keep an eye out for ways to redeem rewards with other airlines, hotels, rental car companies, and retailers. Official partners offer more value per point.

Keep track. Watch over your bounty, expirations, and deals with free programs at websites like Points.com or Mileport.com.

Don't let rewards expire. Account activity may be as simple as visiting your credit card's reward-redemption website to get magazine subscriptions or iTunes downloads. And watch the clock if you want to transfer or consolidate miles among different account holders to reach the reward. Every program has its own window during which that's allowed. Continued...