We're at the halfway mark of 2007. Let's spare everyone the embarrassment of a New Year's resolution review and get right to the bottom line: Are you on track to cash in on those at-work perks you signed up for during open enrollment last December?

With six months of earning, saving, and spending under your belt, you've got a pretty good picture of how the year is going to play out financially. Don't underestimate the worth of what your employer has offered to put on its tab: Benefits represent big dollars -- worth anywhere from 20%-50% of your salary. Yet seven out of 10 of us spend an hour or less reviewing our options, according to a recent MetLife survey. (Good rule of thumb: You should spend more energy reviewing and filling out your bennies paperwork than you do on deciding where to go for lunch.)

Remember what you signed up for in December? Me neither. So dig out copies of the forms you filled out or email human resources to take a walk down pre-holiday-party memory lane.

Some benefits, such as your retirement account contributions, can be tweaked year-round. Others, such as health coverage plans, are typically limited to being changed once a year unless you experience a major life-changing event -- such as marriage, birth, or dismemberment -- during the plan year. Right now, just concentrate on the ones that you can tweak.

Let's go to the tape ...

Stop overpaying Uncle Sam
If you earn a steady paycheck (meaning one not dependent on bonuses or earnings that fluctuate from month to month), this is your chance to stop overpaying Uncle Sam -- any more than you already feel like you are, that is. Many taxpayers have too much withheld from their paychecks -- an average of more than $400 each year. Here are some tips on making sure you're not giving the IRS too generous a tip.

If you got a tax refund of at least $1,000 last year, have made no adjustments to your W-4, and don't anticipate any major life changes or a monster raise, grab your most recent pay stub and last year's income tax return and head to the IRS's withholding calculator to figure out what adjustments you should make on your W-4. To avoid underpayment penalties, shoot for the number of allowances that satisfies 100%-110% of your total tax bill from last year.

Don't underpay yourself (or pass up free money)
Next on your review list is your retirement savings plan. As the months progress, make sure you're not shortchanging your future. Check your contribution balances on your at-work savings plan (e.g., 401(k), 403(b), or profit sharing). At the rate you're going, will you max it out before the first refrain of "Auld Lang Syne"?

The 2007 contribution limits are $15,500 (or $20,500 for those aged 50 and up), not including any matching contributions your boss kicks in. That last part is important. Even if you're not maxing out your account, are you at least contributing up to the amount that your boss matches? That, my friend, is free money. And there's no investment that can guarantee that kind of return. So don't leave the dough on the table.

You can adjust your contribution amounts at any time during the year, so do the math and up the ante. My Motley Fool Green Light co-advisor Shannon Zimmerman (who also happens to be the man behind Champion Funds) has some tips on doing a 401(k) checkup.

Although unrelated to your at-work benefits, now's also the time to think about that IRA. If you haven't devoted any money to it yet, start automating this pay-yourself-big-time-in-the-future account and put it out of your mind. You have until next April to fund your account. So set aside $444 a month (if you qualify for the maximum contribution limit for '07 of $4,000) or $555 if you are age 50 or older (to hit the $5,000 savings ceiling). Even if you can't spare that much cash for the next nine months, sock away something -- $50, $500, or, heck, the whole shebang if you can. Trust me, you'll be glad you did after you retire.

In this month's edition of Motley Fool Green Light, you'll find specific investment tips for each dollar amount mentioned, a three-investment diversified portfolio (a blue-chip anchor, a zippy growth stock, and a value play) as well as Shannon's top picks for cheap (but reliable) brokerage accounts -- if you haven't already set one up. You can read the issue right now by taking a free 30-day trial.

Drain your flex-spending dollars
If you signed up for a flexible spending (medical and/or dependent care) account at work, start reaping the benefits of paying for necessities with pre-tax dollars. Gather those bills you've been shoving in an envelope and submit those reimbursement forms. Then project the next six months of spending so you are sure to drain the account. Some vendors, including 1-800 Contacts (NASDAQ:CTAC), Drugstore.com (NASDAQ:DSCM), and Walgreen (NYSE:WAG), have tools on their websites that help you track qualifying purchases.

Average out-of-pocket expenses for a family of four, according to the Milliman Medical Index, are $2,210, the bulk of which ($810) goes to physician cost-sharing, followed by inpatient hospital costs, pharmacy costs, and outpatient hospital care.

It's important that you spend this pre-taxed money you've earmarked for medical expenses, since most plans do not allow carry-forwards on unspent funds. However, many plans now have a grace period and allow expenses incurred up to March 15 to be eligible for the previous year's FSA deductions. Ask your plan provider or HR if yours is subject to the use-it-or-lose-it provision.

Also make sure that you're getting what's coming to you from your insurance coverage. Keep tabs on your paperwork and stay on top of those health insurance claims you submitted.

Review time well spent
It may be hard to motivate yourself to do a financial checkup with no looming deadlines. But doing so now can prevent trouble that is harder to remedy come December. Consider how much time we devote to other important tasks. According to a Guardian Life Insurance Company survey, on average, American workers spend 1.4 hours reviewing their benefits, 2.7 hours preparing for Thanksgiving, and nearly five hours on holiday shopping.

Think about it: If you spend an hour this month doing a mid-year financial status report, you'll have more time in December to fight the yuletide shopping crowds. 

Motivated to continue?

The Motley Fool offers loads of perks -- like Pop Tarts, Ping-Pong, regular poker games, and 401(k) matching. Mmmm ... Pop Tarts. Dayana Yochim puts the icing on financial advice as the co-advisor for the Motley Fool Green Light service. (Click that link for a free month-long pass and access to $450 of money-making, money-saving advice per month.) The Fool has a disclosure policy.