I wanted a gravity feed option for water delivery from my existing Scepter jerry cans that could also be used as a shower or sprayer for dishes. For $10 in brass parts, a short coiled hose and a garden sprayer, we now have a nifty faucet/sprayer.
Gravity feed only with a relatively full can
I installed a schrader valve stem
Aired to about 25 psi doesn't stress the can much. (The lids don't handle much more than this before they start leaking air.)
At 25 psi it shoots a stream from a garden sprayer about 25-30 feet
Or it creates a nice shower, warm up that water before pressurizing and you're good to go
The proof will be in the field test but it was a fun little project. It helped having my 13 year old daughter able to reach into the can to hold fittings. On the inside is a rubber o-ring and another fitting the create a tight seal for the faucet.