Have a look at the reinkstone, that looks quite interesting. I have a remarkable and a sony. I haven't used the sony since buying the remarkable. Despite the larger size, it is a much worse device. The writing experience really doesn't compare.
An alternative if you want more functionality is to root your sony, there was some progress on hacking the sony for putting regular android packages on it. I can dig out some links if you can't find it.
An alternative if you want more functionality is to root your sony, there was some progress on hacking the sony for putting regular android packages on it. I can dig out some links if you can't find it.