If you thought you wasted some flexible spending account money last year because you didn't spend it all by Dec. 31, you might have a second chance.

But you'll need to hurry. The next, and final deadline, is March 15.

Flexible spending accounts, commonly referred to as FSAs, are popular employer-provided benefits, allowing workers to set aside money to pay for items such as health insurance co-pays, uninsured treatments (such as vision care) or even over-the-counter drug purchases. The money is put into the employee account through regular, equal payroll deductions. Even better, the deductions are made on a pretax basis, meaning you don't have to pay federal, Social Security -- and in some cases -- state taxes on that amount of income.

However, FSAs do have one major shortcoming: If you don't use the money, generally at the end of your benefit year, you lose it. Because of this no-carryover rule, many workers annually forfeit sometimes sizable amounts of FSA money.

Complaints about this restriction prompted the Internal Revenue Service a few years ago to change the rules. Now, says the IRS, spending plan participants can make claims against their accounts for up to two and a half months after the end of their benefit year. If you're on a calendar benefit year that ended Dec. 31, you can use your 2007 contributions for expenses incurred as late as March 15.

The hang-up here is that it's up to employers to implement the extended-access option. The IRS said they could offer the extra FSA time, not that they had to offer it. So make sure your employer does offer the grace period. If so, and you do have some 2007 cash left in your FSA, then you still have a little time to make sure it's not wasted. Here are some ways to empty your account.

See your doctor and dentist now
One of the most common uses of FSA money is paying for orthodontia. Although time is tight, it's worth a try to get into your dentist's office now.

On the other end of the age spectrum, older patients who have dentures can take advantage of the account money to ensure that their dental health is good. Patients of any age should squeeze in another appointment in the next few days, especially if it's been a while since your last visit to the dentist. Since it's a new benefit year, you might be paying to meet a deductible and the FSA funds can cover that expense.

And while cosmetic procedures such as teeth whitening are not allowed, you still can get a bit of a smile boost courtesy of your FSA funds. "One thing you can spend the money on is getting another teeth cleaning," says Donna LeValley-Cocovinis, attorney and contributing editor of the annual "J.K. Lasser's Your Income Tax 2007" guide. "If you can't get the whitening, the cleaning never hurts."

Don't forget about your routine annual physical exam. If your insurance doesn't pay or only covers a limited amount for preventative care, using your FSA to cover it is a good financial and health care move. This could include skin-cancer screenings and cholesterol checks. "Go for a checkup, spend out your account and then know you're OK," says LeValley-Cocovinis.

FSA cash also is great for paying for alternative treatments that are, generally, not covered by health plans, such as acupuncture or chiropractic therapy.

Vision care is another area, says LeValley-Cocovinis, where employer health care plans offer little or no coverage. Your FSA money can be used to pay for eye exams, a new or extra pairs of glasses, even LASIK eye surgery.

"Prescription glasses, especially sunglasses, are expensive, but having an extra pair is useful," says LeValley-Cocovinis. "And don't forget about extra contact lenses, especially the disposable ones."