Assistive Technology blog.

The changeable overlay of this is really cool, since you could use either upper- and lower-case letters, as shown, but also could potentially include braille or other relief texture to allow it to be better felt by those with sensory troubles.
The lighter touch needed for these keyboards could also be of use to those with minimal movement ability.

More importantly, how great are their accents? I saw 'Southeast', but did not first think of the Surrey and Sussex area.