I was always a big fan of the Motorola LapDock. The concept of having a smartphone with so much resources that it can be used like a laptop is awesome. I really think that will be the future.
Think about it.
In your pocket: A kick ass smart phone with all your data and accounts. Insert it into the lapdock (which can be super sleek and light due to being just a screen and keyboard with a big battery) and you have a Android based Laptop (Future: chromebook).
Who needs a normal laptop anymore?
Anyway, Motorola was first to implement this and sold this thing, the sleek all aluminum 11'' Motorola LapDock, only usable with the Motorola Atrix. After that one they shipped two newer models which could be used with most of Motorolas other Android handsets, but this one is the best designed.
I got one cheap on ebay (65€) and as you can see on the right picture, that is no Motorola Atrix in there, that is my Motorola Droid 4.
That was made possible through a tiny hardware hack. All that is needed to do is turning the mini HDMI and micro usb ports inside the docking cradle. All in all maybe 30 minutes work. Some trimming was necessary to turn the connectors around. I don't know why they didn't ship it that way in the first place, everything works out of the box (except volume control if using the speakers in the dock ... which are worse than the one in the phone).
I don't know if I will use that thing much. Its pretty light, thats a plus. Decent keyboard too. I bought it for my Rasberry Pi in the first place but got the idea the moment I had it in my hands.
Some more proof in the picture to the left.
It's sad that Motorola is leaving the whole LapDock idea behind. The newest phones come without support for the docks. I really believe that this is the future. Smartphones are so fast already, in 5-7 years time most people will need nothing else but their phone and something to give the interface more room.
Some further reading