My wife said the magic words: "Do you think it's time to upgrade the desktop computer?"

Well, the answer is "yes" but I think I can squeeze a little more life out of this 4.5 year old machine. What I told her was that the next thing I wanted to upgrade was the case.

And the reason for this that our new house is a dust factory. No idea why, but it's probably related to the wall-to-wall carpeting, and the kitchen remodeling we had done a few months ago. Even after frequent replacement of high-efficiency filters in our home's vent system. The computer collects dust quite efficiently, one reason is that the filters on the two intake fans reduce the flow dramatically so the exhaust fans overwhelm them.

Crux of the story is that dust is sucked in from every time little seam and hole in the case. I could adjust the fan speeds with a controller, but would rather start over.

So with this in mind, I was thinking of either:
-buying a new ATX case that was completely sealed and had a filter system (could be expensive)
-retrofitting the above-mentioned case with seals, filters, etc (could be difficult)
-building a new all-acrylic case that is sealed up tighter than a drum (could be fun!)

Now if I go this last route I would need to find out the following:
-What adhesive to use when putting acrylic pieces together.
-What thickness acrylic to use for the outside?
-What kind of rubber/foam seals to use around:
--optical drive
--fans
--PCI slots
--IO panel
-Will dust get sucked through the CD/DVD drive tray?
-What kind of filtering system to use.
-Will this cool efficiently?

Comments? Suggestions? Criticisms? Witticisms?