Hey, gas canisters are expensive. Why NOT just refill them with cheap gas from a bulk propane tank?
A "bulk" propane tank
Yeah, and on eBay you can get a cheap canister refiller that will do just that.
A very dangerous canister refill adapter
But refilling backpacking canisters with this particular canister refiller is inherently dangerous. Find out the whys and wherefores in my latest post:
Canister Refiller -- WARNING
HJ