Business Cards are 3.5 " x 2".
For some inspiration, check out these designers:
http://www.csadesign.com
http://www.attik.com/main.html
http://www.barnbrook.net/
http://www.cahanassociates.com/
http://www.thedesignersrepublic.com/
http://www.duffy.com/duffy/index.aspx
http://www.miltonglaser.com/
http://www.michaelschwab.com/
http://www.moderndog.com/SWFX/
http://www.samatamason.com/main.asp
