Meccano/Erector is a great prototyping and one-off construction tool.
Here's a device sitting on my desk that I use almost every day.
The mount is resizeable so that any ipod case can slide in and out and be held in place only by friction. This allows me to quickly insert/remove the Ipod before I head home from work.
The back also has a vertical slider so that the viewing angle can be changed.
I enjoy the look of the newer, more industrial looking meccano pieces.