System lock ups

[wax_man@bellsouth.net]

I'm having a rather strange problem with my system and was wondering if
anyone has an idea on what might be going on.  Every so often, the load
on the system will go balistic, and basically lock the system up.  If I
have top running during this time, it will show loads >3; however,
there is never a program running with more than a few % of the
processor.  

During this time, there is nothing I can do, other than switch consoles.
 I can type in one command per console/xterm, but then it will just sit.
 Eventually the system will come back, and be normal.

Does anyone have an idea on what is happening?  Also, is there a way to
get a running log of the load and processor hogging programs (kind of
like top -> syslog type thing)?

Thanks,

Chris