This really don’t makes sense in the 21st century: Being at a networking event and speaking to someone and then at the end of the conversation getting a business card with a name, phone number, email address (and a fax number if a real dinosaur).
Please give me your twitter handler or blog, we are in the 21st century. This information will allow me to learn more about you and interact with you in a conversational way – following up with a call or an email is something sales people do, not people who use network events for interactions and forming of networks. You can also drop your office address when you next redesign your card, I am not likely to ever send you a paper letter.
BTW, when at it, if you give me a business card and there is a chance I will access the information on the card from my mobile phone, please include the info in a QR code too so I don’t need to type it.