I would imagine they'd work well for steadying a wobbly table or chair....
In all seriousness I have no idea what you could use them for. Folks in Europe who use the dongles for watching actual TV in addition to SDR stuff can use 'em but they're kinda useless for the rest of us. They require a device driver of some sort, I do know that.
Maybe some sick genius among us can program one to change traffic lights from red to green or something... that'd be friggin' sweet...
-AZ