My maternal grandfather made his own electric mower from stuff he had around the house. He built a wooden deck (he was a carpenter by trade) and used a washing machine motor with an extension cord. My mom still tells stories about it, but it was gone by the time I came along. From what I've heard it was heavy, under powered, and with a motor that only turned 1750 RPMs, had a slow blade speed and didin't cut well, but it was a freebie!
I had an opertunity to use a modern electric Black & Decker mower about 4 years ago. It was a few years old, but did a decent job on the trailer park sized lot of an old gentleman I helped take care of. There is a learning curve in how to handle the cord, but they would be a decent choice in a place like a trailer park where the lot size is tiny, storage is tiny, and still give a good result. Worked better than I thought it would.
Although I do find it interesting to watch my brother's electric mower (battery powered) running around mowing the grass on its own. When it gets low on power it goes back to the charger and charges its self in about 30 minutes, then continues to finish up the yard (75 by 150 ft).
But since I have two acres, I prefer to use a gas mower.