As far as I know, the Wii doesn't require hurricane force winds in order to cool it down a la 360/ps3.
However, with wiiconnect24 on, it
does get pretty warm.
So, obviously, loadsa 3rd parties are coming up with fans. They're powered via usb and simply extract extra air from the rear vent.
Here is one:
Dual Slot Fan; but in the review, it's bloody loud :(
Here is another:
Single Slot Fan; looks nifty in that it has a through port, and this time only takes up 1 usb slot (there is still room to get to the adjacent slot even after plugging it in).
Can get these off ebay for about £7 delivered (from HK)
Q: anyone tried the second one? I'm just interested to know how loud it is.
Probably won't buy one myself as I don't think they're needed, but maybe useful info for those who may have their Wii's in a confined space (like inside an av cabinet....ie behind "closed doors") and want more "ventilation".