Replace Cisco IOS/CBOS with freebsd - possible?

[Chris H]

Greetings,
I'm RP for a fairly large chunk of IP real estate. I carved out
a /27 segment for my home network. Which is currently running over
a cisco 837 GW (adsl/router). I'm not really keen on it (the router/modem).
So I thought to myself that it couldn't be /that/ hard to build a
box with FBSD that could replace it - am I crazy? Wouldn't it
be possible to upload a minimal build of FBSD to the modem, not unlike
one would tftp a new version of cisco's IOS, or CBOS? I searched
the projects area to see if anyone had tried it. But the only thing
that came anywhere near was netperf. But the only similarity is that it
is network related. Anyway, this seems quite feasable as far as I can
tell. So I thought I'd ask in hopes someone might enlighten me further.
Maybe someones already tried it?

Thank you for all your time and consideration in this matter.

--Chris