Very good idea. Clipless pedals (Shimano SPD M520 if I remember correctly) were on my first decent bike, a Trek 7100 fx hybrid. I am quite sure that it got my love of cycling started, really. It tremendously improves efficiency, I find.

(Although just having stiff sole shoes does make a big difference, to start with.)

Why would people laugh at you? Plus: many commuters do just that.