This submission is more of a general concept than an exact design specification, the actual case detail can be left up to the modder's discretion, regarding time/material constraints. Here is a list of components needed to complete the build.
Thermaltake 7" retractable touch screen LCD $350
2 gig Corsair XMS2 DHX 2048MB Dual Channel PC6400 $ 35
250 gig Seagate sata hd $45
80mm Blue cold cathode fan $11
Plextor PX-850SA-BULK Internal DVD $45
Total cost $486
Ok, so I have a desk fan exactly like the one pictured (although mine is still it's original colour). Looking at it, I can see it would make a great jet engine (sorry, I was thinking small and powerful, like a turbo pc... then I saw a pic of a VW Beetle with a jet engine... how much power do you want?). I am totally willing to donate this fan to the cause, should I be picked as a winner.
Here's the idea...
Once the front/rear cowling is separated, a middle section could be added, to make the whole assembly look like a small jet engine. This mid section would of course house all of the components. The entire case should resemble a very short jet engine bolted to a test bed. The outside can be a jumble of ominous looking tubes and wires... to keep clutter down inside, any wiring can be routed through the case to the outside, maybe enclosed in braided steel hose or something. The exterior will be painted to look like the jet in my accompanying diagram.
Now for the clever stuff...
If the motor to the fan is reversed so the fan blades spin in the opposite direction, it will suck in air instead of blowing... et voila, super cooling. I do require that the guard on the case be left on, as I have a number of very inquisitive cats. It would probably be a very good idea to have some kind of wire mesh to protect the components from high velocity "stuff" being sucked in. The mid section will have the dvd burner and lcd mounted inside, along with the mb and hd. If this section has a hinged opening, it will allow for access to the components.
The "special effects" are housed in the jet nozzle section. A piece of translucent fabric, made into a cone shape, with the end cut off will be the jet flame. If it is attached to something like elastic, or one of them retractable keychain things... it should provide enough tension to keep the fabric hidden inside when the fan is off. Turning on the fan will of course create airflow through the case, making the fabric cone billow out of the back. As air flow increases, the tension in the elastic will allow the flame to get bigger... the 80mm blue cathode (with the fan removed) will back light the fabric, making it glow blue... the fan itself is 2 speed, this can be left as is, or have the speed switch replaced with a variable speed dial.... either way, it should demonstrate that the more airflow, the bigger the jet flame out the back.
I will be using this as a media pc, so really all I need is a small hd, and the dvd (for installing the os... obviously). Any other storage will come from external drives that I have. I'm only going for 2g memory as I am probably going to be using xp (unless Microsoft make HUGE changes to Vista... like rewriting it completely). The touchscreen lcd will be my ui, so hopefully no need for a mouse, keyboard or monitor... and I won't need the tv on should I just wish to use it as a stereo.
Well, that's about it. I hope you enjoyed this idea, and should it be picked as one of the winning entries, I hope you have a lot of fun building it.