>> Some "high speed Internet" setups don't work for more than one
>> machine at a time.
> This should not be the problem, afaik.  It has worked before (I
> should have mentioned this in my first post), and I have heard
> nothing about them changing their EULA to the opposite.

Ah, then that's probably not it.

I don't have any next guess.  I'd have to start tcpdumping and whatnot
to figure it out.  It's not what someone else guessed about broken DNS,
because (a) you specified -n when testing with ping (or at least you
said you did :) and (b) ping printed the "PING xxx (xxx): 56 data
bytes" line, and if DNS wedging were causing the problem that line
wouldn't appear.

/~\ The ASCII				der Mouse
\ / Ribbon Campaign
 X  Against HTML	       mouse@rodents.montreal.qc.ca
/ \ Email!	     7D C8 61 52 5D E7 2D 39  4E F1 31 3E E8 B3 27 4B