Hot Corners are really the killer feature of this machine. Now all of a sudden, any app whose core functions can be invoked with a keystroke can now be invoked via a tap on your trackpad. Right now, I have iClip, Desktopper, and Trampoline all linked to hot corners.

The possibilities are boundless...

Egh. EGH. No. Mouse motion is jerky and inaccurate, and setting it to OSX Trackpad Acceleration doesn't get it even remotely close to what Apple achieved. I uninstalled it pretty quickly after rebooting the computer to finish installation.
I can see where it'd be useful, but I honestly don't like it. The poor behavior was the biggest immediate turn-off, but quite a few things need to be added/improved for me to even think of using it again.

I'll keep my two-finger scrolling and ACTUAL Apple trackpad acceleration. The trackpad behavior of my Powerbook has made MANY PC-laptop-using friends jealous. This app makes it feel like the trackpads I've tried so hard to avoid.

This driver gave me trackpad scrolling on my old G3 powerbook (yeah Pismo!). How awesome is that?! Plus hot-corners. Fantastic.

I hate using a laptop without it...

Without this Prefpane I would be lost on my iBook.

This extension rules

Sidetrack's mappable-corners beat Apple's two-fingered scrolling and right-clicks, hands-down. er, hands-on. or something