Additional rigidity is required to prevent a cheap hose from kinking. This rigidity can be provided by wrapping the hose end with a thin wire and then taping the length of hose with electrical tape.
I only wrapped the ends of the hose but you could do the entire hose if you prefer.
galvanized wire - you can get a whole spool at walmart for like $2.50
alcohol - used to clean the shop-vac hose before taping
electrical tape - or any ductile or stretchy tape (wide is better)
gorilla tape - optional
goop (mult-purpose glue) - optional
shop-vac and an awesomely improved hose (for cleanup fun afterward)
Step 1: A few steps for an improved hose
Pull the hose ends off so you can just work with the flexible inner section. They should be on pretty snug, but a firm quick twist should release the ends (at least for cheap ridgid brand shop-vacs).
Wrapping with wire:
Prepare the wire shape by wrapping it around a cylindrical object that is about 3/4 the size of the hose diameter. it should be a fairly uniform helix after preparing it.
You should notice that the hose is corrugated (textured with concentric rings). Try to twist the hose into the wire helix like a screw. Wire on every other ring of the hose is probably sufficient.
Taping the wire:
Thoroughly clean the parts of your Shop-vac hose that you will be taping with alcohol. I poured a little on a paper towel to rub it on the hose, and then wiped it off with a clean shop towel.
Tape one end of the wire with tape (or gorilla tape for extra strength) and position the remaining wire. Twist the remaining wire taut and tape the other end to secure it.
Snugly wrap electrical tape along the entire length of hose that is showing wire. Use a single length of tape if possible to prevent loose or debonding tape ends. Overlap each revolution as necessary. (I attached the hose back before wrapping the electrical tape so the hose would be in it's regular position.)
Use glue (I used goop) on the tape ends to keep them attached for a longer time.