No Trackpad on the PowerBook 150 according to Apple. Apparently a popular weekly paper publication slipped up and incorrectly stated that the new entry-level notebook computer sports one of the touch-sensitive devices found on the 500-series PowerBook models. In fact, the 150 has the same rolling trackball found on most previous 100-series models. [MHA]
Expose Shortcut for View All Windows
In Expose mode in Snow Leopard, press the Tab key to view all windows belonging to one application (equivalent to pressing F10 or Control-F3 on recent laptops). Press Tab again to switch between applications while remaining in Expose. You can also click an icon in the dock.