I would use the verdex XL6P, as it has 128 MB of RAM, and 32 MB of flash.
Personally, I would just use one of the existing routers that are
supported by DD-WRT or OpenWRT linux based firmwares.
It would be much more cost effective, and would give you a 4-port switch
and wireless. The Linksys WRT54GL is a good one to start with. If
you get a WRT54GS (the older rev ones that still had linux firmware, see
the links below for details), you'll get more FLASH and RAM.
Now questions, I gather the motherboard only has 16 megabytes of
(flash?) ram, when downloading torrents, I dont want this baby to
any way of upgrading, I'd want at least 64 megabytes or ram, 128 to 256
would be comfortable though.
I plan on a debian system, running snmp (mrtg), sshd, cron tasks,
lighttpd (and maybe sqlite memory allowing).