Lots of folks want to go paperless but they feel frustrated because the scanners they already have don't make good enough scans. I've recommended the Fujitsu ScanSnap in the past as a good all-around scanner, but apparently it doesn't do that well with business cards.
It's annoying to have to buy a tool that only does one thing, but for business card scanning, the CardScan is the one to have. Networking maven Valerie Gonyea uses it for her oceans of cards and praises its accuracy. So, if business cards are piling up around you, give it a try.