As a contractor, I change offices frequently depending on my current client. Most of the time there isn't a bike rack available, and I sure as heck am not going to wheel a bike into their building. Generally I'll find something like a tree, fence, telephone pole, sign, etc. to lock up the bike.

At one client location they had none of those available, so I found an out-of-the-way spot in the landscaping and just locked the bike to itself. I was at that location for nearly three years and never had the bike stolen.