Related link: http://www.mobilescout.org
MobileScout - “A Mobile Phone and Web Public Art Project by Julian Bleecker, Scott Paterson and Marina Zurkow” is an interesting website. It took me some time to figure it out, but it is essentially just a collection of observations in the form of voice mails. You can call the phone number, walk through the playful voice prompts, and leave an voice message (observation) on your surroundings. Try it.
MobileScout also reminds me of the Sonic Memorial. The Sonic Memorial was this phone number that people could call in and record what happened to them on 9/11 in NYC. You may have heard the NPR story on this in 2002, if you haven’t seen this site yet, you should. It is another (much more serious) use of the same technology.