I'm in the midst of having something like what Casper is talking about done for me by a friend who is a machinist. Then off to the anodizer, then on top of my case. I can tell you that, if you can't do it all yourself, it won't save money over the TranZPorterZ, but can be done out of anodized aluminum

Mine will be on top of my case with rubber grommets, and so the wiring can run easily into the case avoiding the need for a separate power supply, but I will still have a power cord coming out for the pump.