Here's rather a fetching piece of furniture design. SpoolStool, by New Zealand industrial design student Joe Levy, is something of a mashup of a stool and an extension cable, allowing you to plug a laptop or other device into its underside while its built-in and lengthy power cord, which unspools from around the edge, covers the distance to the nearest available socket.
The legs themselves plug directly into three of the sockets, and one is left available in the middle of the underside to plug into.
Why plug-in legs? Versatility, apparently. Pulled out, SpoolStool basically becomes your common or garden extension cord you can pop onto your desk socket side up. And if a wild flight of fancy takes you, you can even plug in one of the legs, embedded with numerous LEDs, to turn the thing into an improvised lamp.
Though the detachable legs are a fun (if impractical) idea, I personally just like the sound of a handy table with an integrated socket or two and a nice long power cord.