My Logitech Webcam 300 freezes.
Windows 7 machine. Fully patched, Secunia gives 100% secure score. Driver up-to-date, device manager says 'This device is working properly' (It lies!).
Symptoms: Start Logitech HD Vid, or Logitech Webcam and camera freezes. Light comes on above lens, application interface launches with a black screen waiting for a video picture. Machine completely frozen, unresponsive, even Ctr Alt Del does not respond, only way out is a hardware reset - nasty.