I work at a Housing Authority so we have a maintenance staff and thus 2 showers. Its a pretty casual environment so jeans and polo shirt or button down shirt is considered dressy. Its almost all down hill in the AM so not so sweaty at least for the next 2 months. I'll have to see after than though. I figure that I need to at least pick up an extra antiperspirant, and baby wipes to go with my towel. I bring my clothes in the day before and wear full on bike clothing o and from the office.
I'm using a backpack for now, but if I can get a commuter specific bike than I'll pick up a pannier instead. I haven't figured out carrying my laptop with me though as its too big to fit in the backpack, and the laptop bag isn't the right shape for carrying separate. I'll have to pull this off for a while before I am willing to invest too much in my set up for commuting.