It's a great idea, I'll accept that, it's also not new - this has existed in some commercial form one way or the other (various calculators could communicate images & chat freely via the airwaves, Nintendo DS could also seek players within a certain range to do some picto-chatting or game with each other). Radio Amateurs have done this since the 80s, me too... I did it with a Commodore 64 + a home made 1-transistor modem and a walkie talkie, worked like a charm, but hey...it's good to see the kids of today doing something else than chatting on the internet.
1). You may want to check with the laws of your country, transmitting on most bands are illegal and could potentially disturb or disrupt ambulance communication, police or other important communications. Becoming a licensed Radio Amateur the legal way, is a good step in the right direction.
2). There are existing options you can use to chat & send files via radio today, Ham Radio enthusiasts knows all about this, visit your local (ARRL or equal ham-radio club in your neck of the woods).
3). If you want to chat worldwide, you could get a shortwave radio - or satellite antenna with the appropriate transceiver and a packet modem, with this - you can chat digitally, send pictures, send files as long as you have a radio amateur license to do so. Basically you need this to operate on the bands, in most countries you can listen in on radio amateurs communicating via packet-radio without a license, but you DO NEED A LICENSE TO TRANSMIT.
There are many more things you can do, there are a lot of commercially available radios, digital radios and much more. And none of them require the internet.
