I commute - 7 miles one way unless I go the 15 or 20 mile route (less likely now taht I have to be in at 7:30), and we have Fridays off (that's why we have to be in at 7:30). I also ride with the bike club on evenings and weekends. I have lights for when it's getting dark early, but IT isn't Massachusetts -- a few of the riders are nuts but most are decidedly and delightfully MIDWESTERN. We had 32 riders in a line going down the road (at 12 mph - not the tour de france!) Saturday and people just managed to get past us. I'm thinking next week I'll break us up into groups of ten or less so cars can pass one clump at a time...
I know I can get out and back and do a "lap" of a 10 mile route in about 40 minutes so sometimes that's what I squeeze in between One Thing Or THe OTher.