[vicgray]

Any recommendation?

iBook doesn't have any holes underneath it. So, normal notebook cooler doesn't help much.

I'm planning to DIY one.

Just get a fan, like those used in casing, and connect the wires to a USB cable. But not sure how to connect.

[Ω]

Don't think the holes underneath should stop you. My TiBook is the same and I use an iBreeze which is basically two fans underneath, and it makes a world of difference.

Before I bought this I just used a book to elevate the back to increase airflow, but then I started folding so I needed a more 'industrial' solution.

[itguy05]

None. The computer will regulate it's own internal temperature. It will turn on/off/vary the fan and throttle the CPU if it gets too hot. It will even power down if it gets over temp.

In short, I wouldn't worry about the heat. Chances are you will get rid of the computer long before any heat related shortness of life would happen (not that there would be any).

[SSharon]

What temps are you reading right now where you are concerned? I have never even heard the fan on my ibook and I've seen it come close to 130 degrees F. It's on my lap right now and has been for 30 minutes and the temps are 105, 85, 110, and 104 for processor, battery, graphics, PS/ memory.