Here is a pic of one i did ~ 3 months ago. it is a maxtor 8gigger, nothing special (i didn't care if I ruined it, i just wanted it to look cool) I had some extra plexi, etc. the cool part is, I expected it to not work ever again, and it works FINE!!!
All i did to ensure no dust was get a plastic grocery bag i dunked it in water a few times and hung it upside down to try to cleanse it some, then I opened the HDD upside down, put it immediately inside the bag (to try and prevent dust) I messed with the cover then (used hot glue to ensure airtight-ness on the window) , and then put it back on upside down.
The really crazy thing is it survived the whole ordeal I was even able to get the files off in windows from it, I did a surface scan and lo-and-behold, it survived even THAT!!! amazing, at the least.
Very cool at the best
Oh sorry for the crappy quality of pictures, my camera is a peice.
http://hardware.ui3.org/temp/drive2.jpg
http://hardware.ui3.org/temp/drive3.jpg
[edit] Oh i neglected to mention- the power leads go to a 5mm BL00 LED i installed to a 4pin molex

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