The rumor mill is in full swing today as there are rumblings that nVidia is working on an x86 based CPU.
nVidia, who entered into a state of almost open warfare with Intel over the need for a CPU over a GPU, seems a very unlikely candidate to make an x86 based CPU. But there does seem to be some evidence pointing to this.
nVidia has been seeking talent in the x86 marchitecture and has been actively recruiting x86 engineers. Issues with this rumor are retty big though, nVidia has no license to make an x86 CPU and are not likely to get one from Intel or AMD. They could opt to have someone else build it for them (like IBM or less likely the new Foundry Company) but that would not stop the lawsuits from flying.