Nearly four years ago (short by a month) I got an arduino to locally turn a relay on and off for a power strip.
http://www.apolonio.com/blog/?p=1890
I have revisited that project again using a Raspberry Pi 2.
It required a lot more knowledge, and honestly I think I could have done this 2 years ago, but it was nice to take another shot at my old project.
I was able to get this on the network in 2013
http://www.apolonio.com/blog/?p=3332
But this version is more secure.