Keep the Change

As a nation, we're big spenders, not savers. So it figures that banks would invent a way for us to do both at once. Buy something using one of the new cards from American Express, Bank of America and a handful of other issuers, and the banks will stash a cash rebate into a savings account. Shopping and traveling won't replace your IRA contributions, but if you use plastic for gas and groceries, the money can add up.

American Express's One card funnels 1% of all purchases into a savings account that now pays 3.5%. At that rate, if you charge $2,000 a month, you'll have $6,000 in 18 years -- not enough for your child's college tuition, but maybe enough for books. Amex will waive the $35 annual fee the first year and seed your account with $25.

Bank of America effectively puts your pocket change into an electronic piggy bank. Sign up for its Keep the Change program and the bank rounds up all purchases on your debit card to the nearest dollar and moves the difference into a savings account. For three months, the bank matches your deposits 100%. After that, it matches 5% per year up to $250. That's no windfall. But look at it this way: A penny spent becomes a penny saved.