So I am contemplating what I might do this winter to provide momentum to keep my exercise going in the dark and cold. I tend not to exercise very consistently in the winter and think some sort of target to be shooting for might help.

I was hoping some of you could help me brainstorm. I walk for my primary exercise (can easily walk a 10k), love to hike and snowshoe, I have access to a very nice municipal fitness center or private gym for a price I'm willing to pay, I'm willing to consider buying a treadmill for home/indoor exercise, I like to swim but I'm not very good and I haven't done any sort of formal strength training in about 15 years. LOL

Here are some ideas I've thought about in the past or recently:
Training for another Avon Walk (I did 26 miles over 2 days in 2006)
Training to walk a 1/2 marathon
Joining a Masters Swim group
Just setting up or signing up for challenges like I have been here at 3fcs
I have flirted with the dream of doing a sprint triathalon but doesn't seem very doable to me right now

Other thoughts?

Peg

The fact that you are already planning for the winter inspires me to do the same!
If you can find a good 2nd hand treadmill, it's a great backup plan if one of your other options falls through (I'd imagine you get snowed in sometimes where you live? I love my treadmill (free from a friend), and watching dvd's makes the time go fast!
It sounds like you are goal-oriented, but try not to get overwhelmed.. the last thing you want is to set your sights too high & get frustrated. I like your idea of training for marathons, etc... I'm gonna do that too!
You are on the right path... mixing it up will keep things interesting. And if you do Netflix, try their exercise videos if you haven't yet.
You're doing great!

How about taking up a new winter sport? My personal favorite is running my dogs with a big mountain scooter (aka "dog scooter" sport..basically mushing for people like me with 1 or 2 dogs and no snow in the winter). But, there's skiing, ice skating, climbing, and all sorts of other stuff that you can only do in the winter. Finding a winter sport you like can turn winter from a "bad weather" time, to something you look forward to.

If none of that appeals to you, the YMCAs here hold several indoor triathlons at the sprint distance and some longer, or you could just train indoors for one till the weather warms up. I think you should go for the triathlon training. A nice big goal would give you something to work on and help keep motivation high, especially if you sign up for it before the winter weather sets in.

Why not aim for numbers 1-4? By the time you complete them you should be about 2/3 of the way to the last goal.
1-4 will get you ready for the at least 2 parts of the triathlon. And so goal number 5 will be within your reach next time around.