I've had this issue a few times in the past - wondering if it happens to anyone else.

I've got my computer on the floor.  Yesterday, I happened to knock a speaker off the table and hit the PC case.  Speaker was fine, but interestingly, the computer froze.  That is, screen still displayed stuff but mouse/keyboard input did nothing, pulling out a USB stick didn't do anything etc.  Pressing the restart button solved the issue.  Note that nothing actually broke however.

My old PC had a similar issue.  I recall kicking it once and it froze up like that.

Can't really figure out why it would do that - fans don't seem to mind being stopped, and the HDD shouldn't cause a lock up like that...

So anyone else experienced this?