Annual chimney sweeping and inspection is important if you burn anything, even gas in your fireplace. Critters get up in there and if you burn wood and combustibles soot does form and can present a fire hazard. Obviously toxic gases from broken chimneys can be a problem too. Having someone come out to look things over and clean is so much cheaper than a house fire. They will service the damper and everything for you at the same time.
I usually think of it and checking fire alarms (and switching batteries) when the time change happens. It is it is time to switch the direction of your ceiling fan blades too. Hopefully those of you who have had them have had them happily spinning to draw cool air up from the bottom of the room. Now it is time to keep the heat in the room and change directions so air at the top of the room is directed back down. That little switch on the fan housing you always wondered about is for this purpose.
One other warning. When you switch the direction. Lots of gunk on the blades may come down on you so plan on one of the nastier cleaning chores. The ones near kitchens are especially fun. And how pet fur gets on top of the blades amazes me.