y-shaped peeler like this one, http://www.amazon.com/Oxo-Good-Grips-i-Series-Y-Peeler/dp/B0000DAQ5E serrated is awesome if you have/can find it.

I use a peeler too, and sometimes I nuke it for just a couple minutes to soften things up first (poke with fork if you do ...)

A peeler won't work well for hubbards, buttercups, kabochas, and similar squashes. For those, cut in half from stem end to blossom end, then cut each half into half-moon slices of workable thickness (1 to 2 inches). Then, with a paring knife or boning knife moving in a jigsaw motion, cut the flesh away from the peel of each slice, following the curve of the peel.

If you cut off the bottom, you can scoop the seeds out that way, then hold it by the skinny part (for butternut) and peel towards yourself, that seems to work pretty well.

I use the kind of peeler with a wide blade that you pull down rather than the flimsier peelers that peel out. I bought a new peeler and it sang away outer layers with ease making me realize that the old peelers were about as sharp as my finger. New and sturdy peelers are my answer to squash.