I have finished my project of modding my external hard drive's case.
Before I explain what I have done...let me explain how this came about...
Not long ago in this same galaxy...
FAN WARS
Episode I: The Thermal Menace
The great sith Phil has just realized that WesternDigital, a large, heavily populated planet in the external rim territories was beginning to heat up to a dangerous level.

Anywho...The 40mm by 10mm that the enclosure I purchased about a year or two ago has been on the fritz. It's been making noise and generally being annoying, but had still been pumping out the air just fine. About 2 weeks ago, I opened up the enclosure and about burned the skin off my hand. Okay, that's an exageration, but, who cares... So I figured rather than waiting around until it burned itself up and I had to buy a new drive, I would just buy a new enclosure with a fan in it.
Bad idea. Being broke, $40+ for a good enclosure was/is simply too large of an expenditure.
So, I cooked up an idea to just replace the existing fan. The problem is, at just FOUR dollars, it was still too expensive for me to do even that.
Not yet defeated, I realized I still had boat loads of parts from computers I've 'used'...err--destroyed--..
To make a long, boring story short, I found myself an 80mm by 25mm fan. Far too large for anywhere inside the case, so for the past two weeks, I've been modding the case to accept this new beast.
Perhaps tomorrow I'll take some pictures of this sweet new work of "art".
It looks pretty ghetto, which, to me, looks kinda cool...at any rate, the hard drive is staying quite near ambient temp now.