The hi-lift is slow as a "winch" but it will get the job done. I would look into getting a length of chain and a Jack-Mate.
Check out the link:
http://www.rescue42.com/jm8000.phpBack in high school my buddy and I got his dad's F-150 stuck up past the axles in some pretty nasty snow and mud. Like I said it took a while but we were able to get it out of there. With out the hi-lift we would have been walking.
One word to the wise though. When using the hi-lift as a winch you need something that doesn't stretch to hook it to. The nylon webbing recovery straps will stretch and eat up the precious little travel that the jack has. Chain and possibly a synthetic winch rope extension would be good to have along with you.
Just some of my thoughts and experiences.