How to clean up at work after a commute?
In the past, when I commuted to a job without showers (I've managed to luck out recently) I made sure to:


Keep my hair relatively short, as to avoid helmet-hair
Get in early enough that I can have a quick wash in a bathroom sink without too many people around to take notice
Always bring a full change of clothes
Like @curtismchale, leave a pair of 'work' shoes under the desk
Bring deodorant!