Saw this on BoingBoing the other day and it sounded good, so we tried it tonight. It's basically just a blended banana. No dairy, no nothin'. Just a banana and some honey if you want. It's not exactly like ice cream, but as my wife said, it's somewhere between ice cream and gelato. I think it's more like custard, actually.
So here's the recipe: cut a banana into chunks (we used two bananas) and freeze in a covered container. Put the frozen banana chunks into a food processor or blender (we only have a blender and it worked fine) with a teaspoon of honey and whatever else you want to add to your "ice cream"; we added five or six raspberries for color. Blend until you've got a consistency like soft ice cream or a dense custard (see photo below), then scoop into bowls (you'll need a long spoon to retrieve the goo if you use a blender like we did). It's a satisfying dessert and for the extremely minimal effort, very well worth it.