This is sorta old but it's still worth checking out... Elevator "hacking" as an Engadget.com article observes, is, a rather generous term... way generous... But who wouldn't like to be able to go directly to one's desired floor without having to deal with all the others in between? I've tried this on Otis elevators (the brand that seems to have the highest success rate save for the infamous 1992 model) and indeed, it seems to work... Interestingly, the article at Methodshop.com mentions the phenomenon of "placebo buttons", such as in say, cross-walk buttons that aren't really connected to, well, anything! The phenomenon of "Elevator Hacking" deserves similar scrutiny... Is it a placebo or does it work? You'll just have to try it for yourself...
Pressing the "Door Close" button in conjunction with your desired floor will, it is theorized, put the elevator into a sort of "independent service" mode... bypassing all other floors on the way to yours...
Link courtesy of Methodshop.com
Have fun stormin' the castle!