Scarr, what about datarate? What is this being used for? Digital? audio?
I would consider the the nordic 24L01. Sparkfun.com sell small modules (2cm x 2cm) with a chip antenna that give a 'usable' datarate of up to 250kb/s...but if you're just sending the odd packet then it might be overkill. That said, its only 20USD. Would require configuring with a micro though for channel selection etc..
Correct, RFID is primarily used for remote access. It usually sends just a code when the tranceiver is close enough but you did not say exactly what you wanted to do. For a data link, this would not be a suitable choice if your wanting two-way communication.