Winter maintenance before putting bike in winter storage?
Wash it. Dry thoroughly. You can even wax it if you truly love your ride... 
Lube the chain
Lubricate all pivot points (derailleurs, brake handles, etc)
Loosen the tension on the cables and put a small amount of grease on the cable ends.
If the hubs haven't been overhauled in a while you can do that.
Remove the seatpost and if metal apply a light coat of grease and re-insert but leave the seat clamp a little loose.  If carbon fiber, remove, clean and re-insert (no grease).  Remember to tighten again in the spring. 
Inflate tires to full recommended pressure.


Store your bike in a warm place and check the tire inflation periodically. If they deflate and it's cold your sidewalls are likely to crack when you pump them back up in the spring.

If hung, you may want to periodically take it down and spin the wheels (and the crank) and then hang it again. While it's unlikely that hanging the bike will result in pitting on your hub cones, spinning them a couple of times over the months can't hurt.