I really miss having a QWERTY phone in my pocket almost as much as I miss the plain vanilla landscape of mobile operating systems that didn't pretend to be anything other than a phone.
I have been slowly and very quietly working with a Nokia Asha 210. It's a phone that was never really released in the US and is a great starter for anyone interested in reliving their S40 Past. They are solid, cheap and fun to tinker in a nice quiet environment whether it's coding or chatting with friends.
With each phone I provide a shell account on a quiet computer and the experience is designed specifically for this handset in mind. All directional keys are bound in the terminal to switch the tmux windows and out of the box the device will do XMPP, EMAIL, IRC.
What little data I've gathered based on my limited understanding is found here. I encourage people to join in and share pictures of their phones, experiences retro hacking phones: