The CompuTrace solution is available on the majority of business notebooks, being a HP freak myself i can confirm it is available in most probook and elitebook series, while not available in the pavilion(private) segment. Fujitsu Siemens and Lenovo (and probably others) offer it too. It is not free, but should be considered as an insurrance.
Hardware based solution is only way to go ,if the junkie that steals it cant surf porn on it right away, it will be reinstalled and all the fancy software solutions are gone.