Originally Posted by M-Coupe99
I use a backpack when commuting to work (only 14 miles one way). I always wear an armored overpant and jacket over my office clothes and keep two pairs of shoes at the office (light and dark colored) as I always wear motorcycle boots (Sidi Vertigo or BMW Allround waterproof).
OP didn't specify "in the winter", so I'm kind of like M-Coupe. I generally comute only on the S1K on days I "think" it's going to stay dry - which is usually June to October. I'll also ride the freezing days when the streets are dry. I just hate cars and wet roads, they don't mix well with bikes on the freeway IMHO. If there is a high chance it's going to be wet, I'll drive, or ride the K1200GT which has Michelin P3's for meats which work great in the rain.
Anyway, I have to dress business casual. When commuting, A* jacket and Gerbing heated shell when below 50F. Always wear some Olympia armored overpants over slacks (which have seen a couple of slides and still don't show it) and Sidi boots. I keep shoes and socks at work so don't change clothes. Lunch and "stuff" go in a BMW tank bag which has worked well, and if more is needed occationally, then a backpack - which may have some Rev'it rain gear in it if things turn "iffy".
Just wish I had those damn heated grips on the S1K, you lucky bastages who have them.