Jamie Herzlich over at Newsday addresses some of the issues you should consider when creating or ordering new business cards in her "Is your Business Card Hurting your Business?" post.
If you're involved in multiple businesses or are targeting more than one market, you'll probably want more than one business card. I use two separate business cards - one geared toward technical services I offer and one geared toward online marketing services I provide. I found that I really couldn't adress all the services I offer with just one card. Meetings with some prospects call for one card while with others, the second card is more appropriate. I've also found having two different business cards to be very helpful because I have attended networking events where one card was perfectly appropriate while the other was not..
Herzlich points out that the use of color is very chic these days and that the back of your card can be used for listing awards or for your call to action. While both color and two-sided cards cost more, the cost is usually well worth it because these features can help your business card stand out in the crowd and get attention.
Creating/Ordering Calling Cards for Your Home Business