This is a pretty short instructable, but I was pleased with how well it worked, so I want to throw it up and see what other projects it can inspire.
Step 1: Making it
My leafblowers were Featherlite leaf blowers I got from Osh for $70 each. I got them for my kite-powered hovercraft, which we were planning on testing in the desert the day we made this, but unfortunately there wasn't much wind. The leafblowers are advertised as the lightest gas leafblower, and they're pretty decent, although every now and then the spring mechanism that winds the pullstring back up jams and I have to take it apart and poke it a bit.
We used duct tape to mount one leafblower on the back and held the other two. There's not much force on any leafblower, so why make a more complicated mount than you need? After piloting our creation around the desert for a while, we all agreed that you get better performance if you hold the leafblowers close to the ground and pointed slightly downwards.
I'd suggest using a longboard, since they've got more room for both you and the leafblower.