writes "According to a security alert released by Security.Org, the Kensington laptop lock that many of us use and love isn't secure. In fact, it can be opened in 30 seconds after about a minute of practice with a $1 worth of equipment. (A Bic pen, and a pair of scissors. In the interest of giving people some time to stop using the locks, the actual method of opening the lock is left up to the reader.)
To make matters worse, Kensington's 'We'll give you $1500 if someone steals your laptop' guarantee doesn't apply -- because the process of opening the lock doesn't damage the lock or cable."
Mind the source, though -- security.org wouldn't mind selling you a book on locks and safes.