2 port ethernet router running linux?

Hello there

besides Soekris boards, that are somewhat overpriced
due to the PCI and pccard slots on them, do any of
you knows any (really) cheap two ethernet ports box
that I can install and run linux on it?

something like Linksys BEFSR11, but that I can install
linux into?

Corel had this, once, the netwinder. a bit pricey, too,
as any hardware feature over-loaded. my need is a
box like the WL11000 but with two ethernets instead of 
one, if possible bellow the US$100 barrier

Any pointers besides Soekris, mini-itx and SBCs would 
be grateally appreciated

Cheers
!3runo
from Brazil