I'm looking for something like the Micro or Nano (or a clone), but with Ethernet built-in. Has anyone seen a board like that?
I have not seen any boards like that but maybe something like a pro mini and a ENC28J60 Ethernet board would be small enough.
Wow, that Ethernet board is so small!
Arduino shield:
ENC28J60 module:
(Moderator edit:)
Or for those that can't open hobby components dot com website, here's a unit from dipmicro.com
I don't know if you're interested in wifi, or only Ethernet, but these boards look interesting: https://www.spark.io/
Tiny boards with built-in wifi. And cheap! Seems like an awesome idea, but I don't know much about them. Maybe someone else has some experience with them?