Credit card companies are currently fighting amongst each other to get
your debt. That's because personal debt in North America is at an all
time high. The result is loads of 0% APR credit card offers applicable
to balance transfers. So, if you have debt elsewhere, they want it.
That way, when your 0% offer runs out, you'll be paying them interest,
not someone else.
But if you have very little or no credit card debt and good credit, you
can use it to your advantage with a technique called balance transfer
arbitrage. Balance transfer arbitrage is the act of using all those 0% APR credit
card offers to earn money. The basic principle is to deposit each
balance transfer check issued to you into a relatively high-interest online savings account or other liquid investment, such as a CD (Certificate of Deposit).
For example, say you received a credit card offer for 0% APR, 12
months, $10,000 limit. You have the card activated and receive a
balance transfer check for the full amount. You then deposit the check
into something like the Emigrant Direct American Dream Savings Account, which is currently at 5.05% APY.
That's roughly $500 in interest earned on $10,000 over 12 months.
(Though you don't want to cut things that close. Only deposit for 11
months so that you don't miss the deadline to pay back your credit.)
You could also get a CD, which usually earns at a higher rate. You just
have to be able to cash out your investment before the credit line
comes due.
You can read more about the ten golden rules of balance transfers at Your Credit Advisor.