I've never had to commute more than 3-4 miles. That said, I tend to wear lycra shorts, boys' silk thermals (more crotch room for the chamois...) and rain pants. Then scurry to the bathroom to take all that off and put on your regular pants. *shrug* I'll never win fashion awards, but it seems to work.

I rarely have problems getting cold, though. On cold days, I steam after hardly any activity. DGF says it's creepy.