Even teachers weren't too pleased in early 2005 when InCom proposed to test its privacy-invading, attendance-taking RFID badges on schoolchildren, but that hasn't stopped the United Kingdom's Alzheimer Society from considering electronic tags for senile seniors. The Society says many victims feel "'compelled' to walkabout." RFID tags would allow caregivers to efficiently hunt down elusive wanderers. If we're willing to tag old people, why haven't venture capitalists started tagging entrepreneurs? Because they've found a far more invasive substitute that does the job voluntarily: Twitter.