I'll admit I did get serious about a no-noise computer when I saw Apple's cube. Thinking "hey, why can't win-PC makers use the same strategy to make a fanless PC?". Heat does rise, after all. Put some 1" feet on your PC case, drill several holes in the bottom and top, and you should have a pretty darned good plume of hot air rising out the top. It might need some deflecting fins inside to make sure cool air passes by the hottest spots, but that shouldn't be too hard. I like the idea so much that the next PC I build myself is going to include a home made case, designed specifically to create a rising air current thru it. With the 1" or so space beneath the case I can mount the power supply so that the cord comes out the bottom, and it's vents are aligned top and bottom too.
Hey, I succeed with getting about 80% of my PC's sound to disappear with a negative sound! Playing the inverted sound requires careful syncronization (timing) I discovered. Apparently the fan waveform is cyclic, and you have to match it's cycle perfectly to perfectly cancel it. My 80% was just an experiment, and not easy to replicate twice in a row. Timing is everything, it seems.
