If you don't count the cost of me, it has always been profitable as the business costs itself are pretty low. I had zero business goals at the beginning and now it is probably the most popular site in its niche (office design).
The thing most people are interested in here is that I moved from using Adsense to selling and hosting 100% of my own advertising a couple years ago. People seem to like how on-topic and relevant the ads are and that they are static graphics.