If you get the itch to start as soon as the snow hits, then join the club. Nothing makes me miss summer in the yard more than a few inches of snow. It's not even the cold that bothers me, it's the simple fact that I know I will have to wait almost half a year before I can start the silliness all over again. And come September/October, lament all the things I had planned on doing that I didn't, and promising myself that I will, definitely,for sure, absolutely, do it next year (even though I know bloody well I probably won't.)
So I putter with my indoor plants. Maybe I'll plant a few select tomato seeds like last winter, and I'll have the earliest tomatoes ever, like last year with my Galina cross. I read through online cataloges, and make big plans, even though I know I probably won't follow through. Maybe I'll make a small hotbox outdoors sometime in March or April. I'll start swapping seeds with people, and making lists.
Winter sowing is big for some people, but I haven't tried it and don't know if I will.
Right now the big push is to get some Christmas baking done, and get the house in order. I remember reading somewhere a Chinese prediction that the way you spend the New Year's day is how the rest of your year will go. Last year I screwed that up royally, with the messiest house imagineable! And it turned out true!