lukaszthegreat: with desktop you have whole desk to yourself
with laptop most of it is taken by computer and its various cables.
I still have a desktop PC (actually two) as well, and I can't really agree with that. A monitor and a keyboard for my desktop PC does not take less space than my laptop with a mouse (it has the monitor and keyboard integrated into it). And I don't really see much difference whether the USB cable of the mouse goes to the side of my laptop, or the back of the tower PC on the floor. If anything, the latter is more inconvenient, if the cord gets tangled with the power and monitor cables and you have to crawl under the desk to sort it out.
Anyway, I mostly use a wireless mouse (and occasionally a keyboard) with my laptop anyway, so...
The main advantage of the laptop is not really the space savings on a table either, but that it is far more easier to use it anywhere (coffee table in the living room, kitchen table etc.), and put away completely in the cupboard if needed. A desktop PC permanently occupies one table (and sometimes even a whole room) at your home.
Naturally if you have set up a whole desktop environment for your laptop, with external monitors, docking stations, external hard drives, printers, fax machines, telex machines, tube radios, B&W TVs etc., then there are no space savings either. But even then you can still take the laptop out of the docking station, and continue using it in e.g. the living room or elsewhere.