Known as B20 (5>20). Great stuff for our engines but, if you haven't already, you need to make sure your return lines and o-rings can handle it. Mine started leaking pretty quickly after about the 3-4th tank (they were old and tired anyway).
Like ethanol, I'm betting we will see more and more of this at least in the summer and warm places. The local Wal-Mart had a B20 sticker on their diesel pumps for a little while but it is gone now. All of our local Exxon stations offer it but in a separate pump. Unlike ethanol, testing has shown it to have great lubricity although I think it cost me just a hint of mileage and power.
Bob