Common belief has mistakenly held that messages sent from one BlackBerry to another using PIN numbers, rather than using normal e-mail addresses, will bypass a company's computers, thus making these communications completely private since the messages are being sent directly from one device to another.
That was interesting. I had no idea that was possible. The last paragraph sums things up nicely:
...this lawsuit highlights two important points: first, when using corporate resources to communicate, employees should assume that all communications are monitored and recorded -- period. Second, personal privacy when using electronic devices to communicate is an illusion perpetuated by our strong desire to believe that we can keep certain communications private as opposed to a rational belief based on an intelligent examination of the technology being used.