I am a new user so I may not be doing this in the right place or the right way so I apologize in advance. One big problem with multi-touch screens for me is that unpredictable things happen when I reach for the phone in my pocket to answer it. Would it be possible to provide a "shake once to answer" and a "shake twice to hang-up" feature on the N900 and or n8. Maybe such a thing already exists.

There's an app for Shake 'n Surf, and you can cancel a call by turning the N900 facing down, but I don't think there's something out there to answer a call simply by shaking the N900.

Personally, I don't think it's a good idea in case you're walking and get a call. If you were not aware the call was answered, the caller will be able to hear everything you're doing...could be embarrassing if you're discussing business stuffs or some other very personal situations. Still prefer to press a button.

I would think the accelerometer has suffcient linear range that we could distinguish between in-pocket jostling and a vigorous shake, just my guess. The problem I am trying to solve is twofold:
The first, when I stick my hand in my pocket to reach for the phone to answer a call I often accidentally touch the screen in a way that makes something unwanted happen. The second, to touch a specific spot on the screen or anywhere else I have to look at it, which is awkward to do if I am driving (I know I shouldn’t). Also, the ergonomics of smart phones in general are substandard, especially for a person with big hands and fat fingers: slick surfaces that make them hard to hold on to and easy to drop, small screens and small touch targets that are easy to miss. (I don’t know why Nokia hasn’t taken my suggestion that they should make phones like shoes, in different sizes.) So apps that reduce the amount of digital dexterity required for norrmal operation seem to me devoutly to be desired.