The Round Engine is a new engine design being developed by VGT Technologies, Inc. in Alberta, Canada. This is not a normal rotary but instead is called a toroidal, with two continuously rotating pistons, an external combustion chamber and a rotating timing disc. The displacement and compression can be altered during operation by an engine management system. It's hard to visualize exactly how it works without some assistance and their website has a lot of flash files that show the movement of all of the parts. It looks interesting. So far they've built a test unit driven by compressed air and they are in the stages of developing a diesel version which means there hasn't yet been a fully functional round engine as a proof of concept.
The theory and descriptions of its features and benefits sound promising, in fact the list of potential uses is huge, but it looks like there is much work to do. This could be one of those ideas waiting for enough capital to push it forward to success or it could be a dream that never pans out. If their plans come to fruition, they will have a great product that will work on eveything from tractors and airplanes to motorcycles and leaf blowers. I'll be watching to see if anything comes of this.
No matter how much research I do, all of you continue to find things I would have missed. (Thanks, Doug)