In reply to csw:
I'm told the best way to make a sledge out of old skis is to get hold of one of those mini trampolines about 3 feet across that have 6 legs.
Remove and discard two legs.
Fasten the skis to the remaining 4 legs.
Climb to the top of a hill and bounce your way down, very quickly.
Don't blame me when you end up in A&E but it is tempting. I have some old skis, where can I get a trampoline?