Mikita, Ryobi, Black and Decker, and Dewalt, have one, so I imagine Milwaukee might have one soon.
Others from a simple search are Kobalt, Greenworks, Snapper, Worx, EGO, Sun Joe, Cub Cadet, Poulan, Lawnmaster, and Husqvarna.
It's interesting that there are recognizable brand names that are traditionally power tool brands, yard maintenance brands, and also new kids on the block.