I have a wireless network that works fine, for all but one computer. 

This computer is running Debian unstable. It connects to the wireless
network fine, and I can ping the router and connect to its
administration web page...but nothing beyond that. I can't connect to
*anything* beyond the router: not by name (umn.edu, etc) or IP address
(128.101.101.101 is a DNS server at the U).

No other computer in the house has a problem. This computer worked
fine until several days ago. I haven't changed anything in the network
configuration. Rebooting doesn't change anything. The most recent
version of Knoppix doesn't even boot; it hangs when detecting AGP.  An
older version of Knoppix had the same network problem, but the CD was
a bit wonky.

Any ideas what's wrong? Should I demote this machine to a doorstop?

Dan

-- 
Dan Drake <dan.drake at gmail.com>