If you want to be a cheapskate, you will find yourself right at home in amateur radio. They are the original juryriggers of electronics
The amateur radio repeater system will accomplish what you want. The coverage depends on the what the hams in your locale have set up. Some areas link repeaters to cover ranges of hundreds of miles, but these advanced systems typically require some patronage, which is still much less than a cell phone plan.
Many repeaters have an "autopatch" for making local phone calls. This is normally half duplex operation, where like a radio, you can't hear the other party while you are talking.
Bear in mind the major differences between a cell phone and a radio: You have zero privacy. Your whole (ham) neighbordhood will be listening to your conversations. The other, possibly more painful side of that is that you have to listen to everyone else's conversations as well, if you don't want to miss a call from someone. There are technologies for selective paging if you have the right (interoperable) equipment
. If not, it's like listening to VHF16 for calls but longerwinded.
This can also be an advantage if you want a group conversation. People can jump in to help you unexpectedly. You jest about it being a different world from a forum, but in fact it is a bit like a forum, but in real time. This also adds a big emergency
application component to it.
Amateur radio repeater - Wikipedia, the free encyclopedia