Computer science students at UC San Diego have written a program that can duplicate keys from security camera photographs:
The team demonstrated the software at ACM's Conference on Communications and Computer Security 2008, where students showed off the technique up close and from afar. They took close-up shots of keys with a cell phone camera. Then, using a 5-inch telephoto lens, they stood on top of a building and took photos of keys sitting on a table 200 feet away. In both examples, they were able to capture sufficient data to create duplicate keys.
http://blog.wired.com/gadgets/2008/10/ucsd-software-a.html
Just think about it. All a thief would have to do is take a photo of someones keys while they are not looking and they have instant access to that persons house or car...scary.
The fact of the matter is that if you are buying a cheap lock and expecting it to protect you adequately, you're wrong.