I think one of the things that keeps people from commuting to work by bike are the subtle details. One of the biggest keys is having an employer who is accommodating to this style. I am lucky in that health and fitness is important to my boss and he understands that healthy , exercised employees work better and are more efficient.
How to dress, change and store the bike then become easy to figure out. While it definitely varies from workplace to workplace it can be done. In my office space I have added a false wall with a cubicle divider to hide my crap behind. Granted, I have the luxury of a little extra space, but it works well. I keep a small luggage bag with clothes and shower supplies there as well. This way I do not have to lug clothes and risk getting them wrinkled each time. And I occasionally change behind it. A small shower located in the building is where I clean up and in about 10 minutes I can be at my desk, all set to go. I have really enjoyed riding to work for a number of reasons. I burn about 800+ calories each way, get some good miles in, reduce the stress level and add a bit of adventure to the day. My only regret is not living closer to work so that I could go right from door to door with each trip. I have a video I made this past week showing a little bit of a typical ride. I hope to get that up here soon.