Despite the fact, that there are already some Quadcopter and Tricopter designs out there (see Mapmaking Quadcopter, Quadcopter), the creator of this Tricopter accomplished to build a fully functional and quite agile model without spending more than 100$. Even the cheapest Quadcopters cost at least several hundred dollars. His Tricopter design builds upon cheap body parts from a local hardware store, such as a wooden Tricopter body. [via Hackedgadgets]
MIT researchers recently published a video of their highly agile autonomous plane drone that is able to navigate through indoor locations. Their video shows a good overview how the autonomous plane is able to automatically build a navigation map out of a laser range finder scanner and to find its way through indoor locations.
Traditionally, these environments have been dominated by quadcopters or similar air drones. The minimalistic design of this plane allows low cost survaillance tasks within indoor locations, such as parking garages, as it is shown within the video below.