Hi, Ronin. The most effective way to cool your Powerbook is not to let it get so hot in the first place.
Maybe the most important step to take in that direction is never to rest it directly on any soft surface while it's in use, including your lap. Any soft material that you set it on presses against the bottom of the Powerbook and insulates that surface, preventing the Powerbook from losing some of its heat there, as it's intended to do. Allowing unimpeded passive air movement underneath the PB at all times goes a long way toward keeping it cool. Your laptop cooling pad will probably make a dramatic difference, especially if it has a fan built in. But even something as simple as keeping a stiff panel of plywood, Masonite or Plexiglas under the Powerbook when it's on your lap, thereby allowing a little air to move through the small space created by the Powerbook's rubber feet, makes a significant diffference. And if you've lost any of the rubber feet, they can be replaced with self-adhesive feet from any hardware store — the higher the better.
When the Powerbook is on a desk or table, raise its back edge an inch or so by resting it on a rubber eraser or something else that's not slippery. The sloping wrist rests and keyboard will be more comfortable to type on, and the slope of the underside will promote convective air movement for cooling.
Use canned compressed air from time to time to blow out the area under the keyboard, after releasing the keyboard catches and flipping it gently back onto the wrist rests. This will prevent dust that is drawn in through the left side and rear vents by the fans from clogging the fins and tubes of the heat sink.
Many Dashboard widgets are huge consumers of processor cycles and thus big heat-generators. If you don't really need them, turn them off. Minimize the number of nonessential background processes that are running on your Powerbook. If you don't use Find By Content searches, turn hard drive indexing off. Use your cooling pad when you watch a DVD movie or stream video off the Web. All these steps will reduce the amount of heat your Powerbook's fans need to dispose of, prolong its life, and increase your comfort when you're using it.
