IgorPlugUDP is an ethernet-enabled infrared receiver. This is an old hack that kmmankad brought up in the forum.
What makes it really cool is that the ethernet is bitbanged using nothing but the bare pins of an ATMEGA168. It is transmit-only, it cannot receive network packets, but that’s enough for a lot of projects.
I’d rather use the Ethersex firmware for this purpose, as it can do a lot more.
But you need a real media access controller for Ethersex.