Try concentrating on up and coming trends. 3D is a big one at the minute for example and were seeing a few hand regs related to 3D technology in the hope that the industry continues to grow and the domains will turn into gold mines!
I would avoid the Olympics as an up and coming topic at all costs though, as they're being really aggressive about protecting the trademark and all related terms!
April
Start with a topic that you know something about. Build a blog with some targeted content and monetize. This could produce some kind of revenue to begin with and offset your costs of experimenting in other niches.