When I first got a mouse in 1991 or thereabouts I instinctively tried to put out a candle in my room by dragging the mouse off the screen. Took me a second or so to realize it wasn't going to work.

(That thing was cool, logitech 3 button bus mouse, came with it's own programming language and TSR you could use to give any dos program mouse support by turning movements/buttons/chords into key strokes and you could even program your own text pop up select windows for more macros. I think the thing came with a 300 page manual. Can you imagine a mouse coming with that now?)