The RS485 chips are easy to use. No microcontroller communication required.
I've used these recently - http://uk.rs-online.com/web/p/line-transceivers/7327958/
They just need 5v, gnd, and the data signal input. This outputs a balanced signal pair which goes down a twisted pair cable. The same chip can receive this signal and convert it back into the original unbalanced data.
I've tested over >120m of cat5 but apparently you're good for >1000m