Why I have a Satellite 1950
Why would you want one?
16" screen with 4:3 aspect ratio, more vertical space is better for software development than horizontal (I can see more lines of code which is more important than being able to watch movies on an airplane).
But you were asking about the keyboard weren't you?
A removeable keyboard means you can sit back comfortably instead of hunching over the laptop to be able to type. Not to mention being further from the screen is easier on your eyes.
Then there is the fact that you don't have to carry a seperate keyboard around with you as was suggested, it may not weigh much but you still have to go through the hassle of packing and unpacking it and finding a good place for it in your bag. An extra keyboard is just a needless pain.
As to how it would be accomplished with no cables?
Toshiba did it with radio frequency I think (I might be wrong on that) and the wireless mouse may be infra red (but I could be wrong on that too, I know it has an infra red receiver but maybe that was for something else).
It has a small rechargeable battery that charges will the keyboard is "docked" and lasts for hours disconnected (days if you aren't playing games with it).
The range is good for several feet and there are a couple channels in case you sit next to someone using the same laptop.