I have designed a standard base that I keep all my NXT bricks on all the time. It works great, it’s very stable, and allows easy access to all the ports. The NXT can be easily pulled off to change batteries. The best part is that it puts the NXT screen at an angle that makes the screen easy to read when working at the computer.
If you look at my Flexpicker, you will see that I used a similar mount to hold the bricks.