The Asus Eee PC 1000/1000H/1000HE all had support for multi-touch trackpad gestures. For instance, while most older touchpad let you scroll through web pages and other documents by moving your finger to the far right side of the pad, on these models you can scroll simply by placing 2 fingers on the touchpad and dragging up or down. For some reason, Asus decided to disable this feature on the newer Eee PC 1005HA and 1008HA models, while keeping other multi-touch gestures like pinching your fingers together or pushing them apart to zoom in some applications.
But a number of users have found ways to enable 2-finger scrolling on these new models. One method involves installing a third-party app, while the other method involves hacking a Synaptic touchpad driver. You can read more about these tricks in two posts at the EeeUser Forums: #1, #2.