Here is an interesting technology: StickyBits . You can scan any bar code with your iPhone or Android phone, add a text, comment, photo, or video and publish it for others to see.

Here is how it works: First, you have to download the application. Then, you scan the barcode, attache a comment, video, picture. The message is geo-tagged and attributed back to the user's social media profile (currently, using Twitter and Facebook links) and it becomes part of that object's content stream. The barcode is either purchased from StickyBits, printed out, or just off the product.

Some worry about the invasion of privacy by third-party applications to your Twitter and Facebook profile. Yet, once you are "out there", you can't turn back. People can see your tweets without special permission, and Google does give a short summary of your Facebook profile. How much is too much? That is a personal question; it simply depends on how much you want to learn about new technology. But, if you want to try any new application, you will have to disclose some information (i.e. connect to your Twitter and/or Facebook profiles).