My mower and edger are both gas-powered. The mower is a Ryobi I picked up at Costco when I bought my house in 2001. Has a Briggs & Straton motor and still runs fine. The mower is not self-propelled and I have no trouble pushing it around. It's sort of a form of exercise. :-P
The edger is a John Deere that I bought at Home Depot. It takes different attachments.. one has the nylon string and another attachment makes it very easy to edge the side of the driveway and sidewalks.