Anyone involved in any sort of development do know that the sandbox environment is one which they relish setting up. As a kid I remember my father always stressing that in a mathematical problem the answer will revert back to the question hence give importance to the testing may be that's the reason I always got first class (+60%) all thru out the academic career because I was invoved in testing the answer, resulting in not answering the whole questions.:)

Well my previous test site was really a rudimentary one with a crossover ethernet cable connected ofcourse between 2 pc just to test out the network programs.

Now it's like a small network which somewhat emulates the realtime network environment. It has everything from the webserver, dns, drupal, qtnetworking, asterisk, hotspot, Gr8t.
It's really easy to setup with EHCP which is a hands off installation process to get you going.