Comment 44 for bug 276445

i never got back to it because i set my router to 802.11g in order to get a freeze and try lamos' solution..
Strange thing though, i never got a freeze.. so, i don't know if something i did accidentally fixed the problem, or if a fix was issued in an update..

i set it back to b and g to see if it makes a difference, if so i will report back (my guess is i won't get a problem)...

@Michael: i have a feeling that you might have a different problem... or to be more precise, you might have this problem, and another one as well, since all of these posts have at least one thing in common: they're related to internet activity.. if you disable that, i think there's no reason for you to be getting this particular problem..
The symptoms (not responding to anything and caps lock flashing) is a kernel panic and it's what happens when the kernel crashes (i think it's something like the "blue screen" of windows), so it doesn't necessarily point you to a specific problem..
(i don't consider myself a Linux expert, so i might be wrong)

in the meantime, try gpowertweak (install it by running sudo apt-get install powertweak-gtk).
This will not fix your problem, but there is a setting (under kernel->logging) that will reboot your computer after a kernel panic.. This just might be a little safer than a hard reboot (turnig off the power)