I don't like the idea of casual experiments where attaching jumpers straight to GPIO pins is a common activity. I would actually prefer the Raspberry board remain safely affixed to a lab-board, with a separate break-out panel/board for the GPIO lines.
My first thought is a cable from the GPIO 'plug' on the Pi board to a panel of sockets (the 21st century equivalent of 'banana plugs' for jumper leads, and my second idea is to break out the GPIO contacts onto a type of breadboard, with multiple connection possible to each GPIO line.
E.g. the Raspberry site has a number of practical examples of attaching simple components directly to the GPIO pins on the Pi board. I would much rather run a jumper from my patch panel to a breadboard, and mount the component on the breadboard. This way the main Pi board remains untouched and safer during a lab session.
Has anyone built anything like this, and if so, what did you use? Being an electronics enthusiast I would prefer to build my own 'lab board' for the Pi than just buy whatever I need.