Hi Alan!

Check out the RIVO at http://mobience.com/rivo

There is also a podcast demonstrating all the functions being performed by
this keyboard, that is only slightly larger than a credit card. 

I believe it is the most convenient. I also have a Verbatum blutooth
keyboard which is capable of performing almost all of the functions the
Iphone offers, but it is a folding keyboard, so you require more time to
unfold it which makes the RIVO seem more convenient.

I have also seen positive reviews of a solar powered keyboard. The brand and
model escapes memory for the moment, but I guess my point in all this is
there are so many options around that it must be clear despite the claims
about on screen keyboards being so wonderful they're obviously proving to be
a bigger problem for more than blind people. Hope you find a good one soon.

73,
Dave