Between paying a stream of monthly bills, buying groceries, filling up the gas tank and managing countless other daily expenses, it's becoming more and more difficult for the average American to save for the big things: a college education, a new home, retirement.

Investing is one of the best ways to build up a comfortable financial cushion over time, but it takes diligence to allocate money for an investment account on a regular basis. Fortunately, there is an easy way to tuck away a few dollars, without even thinking about it, every time you shop.

To help people become more disciplined investors, Vesdia Corp. offers an easy savings program called Stockback. Through the program, shoppers earn unlimited rebates on the everyday items they buy from a network of more than 500 participating merchants, including 1-800-Flowers, Eddie Bauer, Hickory Farms, The Sharper Image, Media Play, Illuminations, Barnes & Noble and Sam Goody.

People participating in the program can choose to have their rebates sent to them via check or deposited directly into an IRA, mutual fund, money-market account or virtually any other savings vehicle they choose.

In the past year, Vesdia also rolled out a Stockback Loyalty Rewards Card that lets cardholders earn rebates of up to 2 percent every time they use the card -- no matter where they shop. Using the card at Stockback's participating merchants earns additional rebates of up to 7 percent.

And to make it even easier for its members to invest, Stockback recently formed a partnership with ShareBuilder, an online investing company.

Through ShareBuilder, investors can conveniently purchase stock for a low transaction fee with no minimum investment requirements. ShareBuilder Securities is an independent broker-dealer and member NASD/SIPC. Simply choose the dollar amount you want to invest in particular stocks. ShareBuilder will then buy the stocks at current market prices and let you know how many shares you've purchased. Stockback members earn an additional 2 percent when using the Stockback Loyalty Rewards Card to pay for ShareBuilder Investing Program monthly subscription fees.

Anyone can join the Stockback program for free by completing an online membership application. Once you submit your application, you can begin shopping and earning immediately.