The Best Ways to Spend $100

In Spanish | Check out gift-card exchange sites — like giftcardgranny.com or Cardpool.com — to sell or buy unused gift cards at a discount. With $100, you could net a card worth $120 or more, says certified financial planner Dannell Stuart of Mission Wealth Management.

Buy 20 baseballs, a blue ballpoint pen and two tickets to a nearby minor league baseball game for a potential major league profit, says Financial Safari's Pete D'Arruda. During batting practice, have your photo taken getting balls autographed by many players. Former Triple-A player Evan Longoria's ball fetches up to $195 today.

Save energy with a low-flow showerhead for under $30. "If there are three people in your house who typically take 10-minute showers, it could save you up to $170 per year," says Chandler von Schrader of the EPA's Energy Star program.

Spend $20 on a digital tire-pressure gauge and $80 in quarters for air-filling machines at service stations, suggests expert Carroll Lachnit, Edmunds.com. "You'll save $130 a year in fuel costs by checking your tires once a month and topping them off to the correct pressure."

Use that $100 to scour garage sales for Zippo lighters. Why? Because collectors covet vintage lighters from the pre-disposable era. The most popular ones — like very early models with the hinge on the outside — can go for $2,000 or more on eBay or HipSwap.

Stamps have been rising by about 1 cent per year. At the current 46-cent rate, $100 buys 217 Forever stamps that you can use even when rates go up. Mail five bills a month, plus 50 cards, and save nearly a buck a year, or $10 by 2022.

A home garden can pay off with savings on fresh produce. Tiny 1-ounce packets of herbs can cost $6 each, or $90 a pound. If you reap 3 ounces every two months for six months, then that's a return on investment (ROI) of more than $100. "Fresh herbs give you a better product and offer financial return," says star chef Robert Irvine.

For $100, a five-year Global Entry membership gets you expedited screening through 30 participating airports. Membership means you bypass hour-long lines (with shoes on) for a major time saving. "If time is money, and happiness equals ROI, this is gold," says USA Today travel editor Ben Mutzabaugh.

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