On many sites in the blogosphere and forums I have read about complete iMac exchanges by warranty, purchase of dehumidifiers and a lot of blind sticks to deal with the problem of fogging on iMac glasses.
The solution is so simple that it should come in the instructions since it does not require anything special.
It is not a solution to the problem, it is about cleaning the glass in a much more comfortable way.
The glass of the iMac is attached magnetically so we only have to pull it, for this we will use a typical suction cup used to hang rags from kitchen tiles or the suction cup of a car GPS cradle; any type of suction cup will do. (If you don't have a suction cup, use cellophane, making a makeshift pull in the middle)
- We stick the suction cup in a corner of the glass and throw
- We wash the glass in the kitchen sink (with a cloth to the mist formed, it is ok but we already take the opportunity to clean it)
- we dry it with a cloth or let it dry where the dishes
- we put the glass back in place
As easy as that.
Granted, the problem comes from a design flaw in the iMac but I think the solution is so simple that, at least for me, it's not worth fighting with Apple.