just was reading Harald's weblog where he writes that there was so much feedback on his A780 hacking and that people are all over it. Some how people seem to want to be able to have a fully controllable mobile phone running software they can change them self. I myself wanted to have this forever so I started working on the Linux port for the HP iPAQ h63xx which by the way makes some progress. The phone is still not usable (which is more of an audio driver issue then a GSM issue) but this should be fixed soon. Also there are other projects (like the HTC BlueAngel Linux port) which all ready support making phone calls. They even have a nice looking phone GUI!
Anyway I think phones running Linux will be one big thing in the future (or at least in the future of hardware hacking, like the Linksys WRT).
Also I started putting to gether a OpenPhone website some weeks ago... but this is work in progress!