Most of the about us page puts the purpose of the startup, then the team, background of company, etc. But when you are just one person, no office, and sometimes history of the company is not so fascination even. What do you actually recommend to put? You don't wanna look small, yet you want to be honest and not to look too big. But ambitious is the key. How do you make people feel that this company is gonna grow?
I think you should write a bit about you and why you have founded this company. What keeps you driving. Are you a coffee or tea drinker. One man shows should - for my taste - should have a very personal touch. I want to know about the people behind and why I can trust them. Otherwise i could go to a big co. I guess if you have this and a short description were are you heading to - that would be enough for me.
If you would have a blog - that would make me feel you have growing company. Of course you should try to post at regular basis there.
John Saddington (who writes about building blogs) suggests starting with a bit about yourself and following with clear information about how the reader will benefit from visiting your website. You can read that here: http://tentblogger.com/about-page/ I think this advice translates perfectly to a business. You want to make your visitors/customers understand who you are as a company...even if you're a company of one. You can do this by sharing some of the history of the company, or simply by adding personality to your copy.
You definitely want to be sure that the customer leaves your about page understanding the benefits of your company (or your website) and how they can reach.