I'm not sure if they are considered startups per say, but I've started two profitable companies while working a day job (to the point where I could quit my day job!) http://www.AUsedCar.com and http://www.BudgetSimple.com . I should say I also created a failed startup during that time. The biggest difference between the successes and the failure were that the successes did not require me to answer phone calls, make sales etc... In other words, completely passive income businesses are the easiest to do with a day job.
I'd be interested in talking about BudgetSimple and some specifics of tactics and implementation if you have the time and interest. Handle at whitetailsoftware dot com.
It's very difficult to compete with the big names, but even .01% of a huge market adds up to something significant.
edit I should also say I started this a LONG time ago, so I have a long tail SEO advantage. I wouldn't envy anyone trying to start a used car site today.
How much did that discourage you in the beginning (the thought of it being extremely hard to compete w/the big names)?
I ask b/c I've been developing an app of my own and this is one of the doubts I have. I love building stuff too much to let that stop me, but it's still something I think about from time to time.
Well the beginning was 1995, so I was competing with Newspapers and Weekly Magazines more then websites. People would refuse to let me list their car for free because they were scared of the Internet.
