KisMac is a free and open source Wardriving application, like NetStumbler for Windows. I can use it to accurately find open wireless networks while I am on the road. This is known as
Wardriving.

KisMac is especially effective with a GPS unit and can even link to Google Earth with the .kismac Google Earth server. With the Google Earth plug-in, I can map out useable wireless signals and even share this information with other KisMac users. This takes Wardriving to a whole new level.

Even if I don’t have a GPS unit, I can view all the other logged KisMac entries in Google Earth.
I bought a MacBook Pro a few months back and found I can scroll using the trackpad just by touching two fingers side by side and moving up and down. Hopping onto older laptops is a drag. iScroll brings two finger scroll on all pre-2002 G4 PowerBooks and iBooks, running OS X 10.3 or higher.
Beta testing now, so it’s free!
Download iScroll2 from VersionTracker.
SlimBatteryMonitor is a customizable battery monitor for the Menu Bar. It replaces the existing one with a monitor that even tells you how much time is needed to charge the battery. The icon takes up less space, runs in the background and will be visible only when you want it to be.
For good battery performance of your iBook, Powerbook or MacBook, make sure you try to consistantly charge and discharge the battery the entire way. Do not leave your laptop plugged in for extended periods of time. Follow the instructions in your User Manual for how to reset your battery’s charge.
Download SlimBatteryMonitor from OrangeCarb’s wesbite for free.