The RepRap team introduced a simple breakout shield -
The Arduino Breakout Shield is a shield that plugs into an Arduino and provides all the Arduino pins as screw terminals. It is perfect for semi-permanent Arduino projects, or just general prototyping. It provides access to all the Arduino pins, as well as providing extra GND, 3.3v, 5v, and Supply voltage pins for convenience.
Those terminal blocks can be quite handy, a bit reminiscent of the Make controller’s setup. – Arduino Breakout
What I’d really like is someone to make a board that has enough power and ground pins for each and every analog and digital pin. Then I could (given that I am within the amp range of the arduino) plug in as many sensors, lcd’s, etc. as I want without making a goofy power wiring doohickey.
… In all likelihood I’ll end up making it myself.