Winter here in NZ and its really tough... I have been jumping on the trainer every evening and watching the Tour highlights while I spin for 30-45 minutes
But its difficult when the days are short, work is a half hour away when driving and I am tied to being a taxi to and from school

I try and do some spinning on Saturday morning
I usually go for a Sunday afternoon jaunt - about 40 kms (about 28 miles)

In Autumn and Spring when there is a bit more daylight, I try and ride to work twice a week (Mondays and Fridays) - more when I don't have a class to teach first thing on the "middle" mornings (just over 25km- nearly 16 miles) - on summer and autumn days when there is plenty of light I like to ride home as well

Otherwise, when there is still evening light I try and do a spin or interval session for a little while after work