We bought a lot of bits and pieces for the trip, so far one has proved to be especially good and one especially bad...
The good gadget is the Thermic boot dryer. This is like a small hair dryer with two legs that you drop into your ski boots and that gently dries them out. I found that if you dont get your boots properly dry each night then you end up feeling colder than necessary the next day, I used to pull the boot inners out each evening and stand them in front of the radiator but that was a lot of effort and this gadget pretty much removes the need for it.
The bad gadget is the pair of "cat tracks". The idea of these is that they prevent you slipping when you're wandering around in your ski boots; they do but they're a bugger to put on and take off. I think the problem is that they come in one of two sizes, small or large and that if your boot isn't exactly in the sweet spot of the size you have then they're a real pain to pull on... Anyway, we used them once...