I wonder what would happen if you put 220v applicances in a 220v socket with a 110v->220v transformer in between. I doubt it'd be good.
You mean a 220v appliance in a 110v socket with a 110-220v transformer inbetween? It'd be o.k. if the transformer is hefty enough to handle it (the wattage requirements) and it can handle the frequency difference (if it matters). Few are. H.K. is one of the places where you can buy these hefty transformers (for tvs, stereos and the like).