>Did you want to do actual ISDN telephony stuff? Or just route IP packets?

Mostly routing IP packets.

>I've always thought that using a TA instead of a router for the latter was
>silly, because of the interrupt overhead.

Well, if you've got a spare machine, then I don't think it's _that_ big of
an issue ... you might add a bit to the latency, but I don't think it would
be noticable with a decent serial card.

However, after looking at prices, I see that ISDN routers have _really_
come down in price, so I think that's probably the best thing to get after
all.  Thanks for everyone's suggestions!

--Ken