Tikitag hasn't been in prominence lately but the Alcatel-Lucent company made a pretty significant debut at DemoFall. In fact, the RFID tagging system will go into public beta soon and it's looking promising.
Tikitag is boasted as a system that will "build the Internet of things," and that assertion is pretty close to the truth. In fact, it will allow you to add an RFID tag to just about anything in the world around you. Once tagged, you can then add a website address or an application to the tag. So, you could tag a business card to lead to your website.
And come October 1st, you can get the Tikitag for yourself for $50. Ten tikitags come with it, as well. You can purchase boxes of 25 tikitags, if you'd like to really go on a tagging spree.