I have to say that I just walked in to the O2 shop last time that I was due a free upgrade and asked for a phone with a 3.5mm jack, got a bog atandard Nokia and put in a larger mini SD card, which I now use with a nice set of Sennheisers and otherwise plug in to the car stereo.
This seems to meet all tahir's specification in a very compact package. Mind you some months pass when I've made or received no phone calls.

N.B. the manual says itdoes emails, but I've never tried!