Got some good replies on my discussion on gloves, time to talk about feet!
I have yet to find a system I'm happy with. Every steelhead season, when the water gets quite cold, I freeze my feet off. Does not help that I primarily spey fish for steelhead, so the entire time while fishing I need to stand in at least a bit of water to get an anchor for my cast. This does not help with cold feet!
I've tried the hot pocket things. They feel great leaving the house, walking to the fishing spot, and so on. However once fishing the ice cold water is too much for them. They can not warm my feet through the cold winter water.
My best system is to wear some serious a** socks. I have a pair of Simms wading socks, the thickest ones that are thick like oven mitts. They are pretty damn warm! Under them I wear a thin pair of merino socks. The 2 socks together generally serve me quite well. But when the weather gets really cold my feet will still freeze eventually.
The only thing I have yet to try I can think of is a pair of electric socks or insoles. I figure cant hurt to buy a set from cabelas, keep the box and receipt, and if I don't like them just return them. Has anyone tried these?
I would lean more towards the socks over the insoles as I wear custom orthotics in my fishing boots as I have gimped up feet. I can fish with whatever insoles but my feet and back will suffer a bit.
Any other tips I'm all ears! Generally I just fish until my feet are numb, go for a bit of a walk, get some blood flowing, take a break and enjoy the fresh air, then back to fishing until back to numb feet again.