ha, that's very interesting: since starting the chat with my friend on facebook (a developer in china) for about 90 minutes i have had *three* lockups (each time recoverable with ctrl-alt-f1, ctrl-alt-f7). one in particular the cursor moved off-screen for a fraction of a second and back again (which is enough to cause fvwm to move very rapidly from one virtual desktop to the next, requesting a complete refresh obviously)
now, it *happened* that, at the exact same time, chromium was again hogging CPU resources. it would appear that the increased CPU usage is the "vulnerable to lock-up" time. hmmm.... :) l.