If you have excellent credit, the credit card companies really want your business. In order to compete with one another, some cards offer excellent welcome bonuses just to get people to sign up. If you're willing to do a little homework, the perks can really add up. Companies like American Express (AXP 0.07%), Capital One (COF 0.66%), and Barclay's are offering some amazing sign-on bonuses, so why not take advantage?

Responsible spending is the key
But won't having too many open accounts hurt my credit score? Not necessarily. According to myfico.com, the average "high achiever" has a total of 4-5 open credit cards, but only uses about 7% of their credit limit. The number of cards you open has very little importance, as long as you don't carry too much of a balance.

Below are some of the best introductory deals you can take advantage of.