This image, from Gizmodo, shows the very simple fact that yes, Macs can lock up, crash, s#%t-the-bed, etc.
According to the Gix post, this is an iPhone display at an AT&T store. The system is a Mac computer running whatever Mac OS. The displays used to run XP.
The gray box in the center of the display is called a "panic" message. Something about the system halting. Interesting...
