My better half has managed to damage her mobile more times than I care to remember. The damage usually involves the antenna socket; until Christmas, she had Ericssons of various flavours. The repair usually involved super-glueing the brass insert back into the (cracked) case, or replacing the case if it could take no more repairs. I came to accept that at the bottom of a woman's handbag is a carefully hidden mechanism which detects mobile phone antennae, and carefully applies as much force as is required to detach it. The mechanism infallibly detects the most inconvenient time to do this.
My finite patience ran out, and I bought her a Trium 110 from Amazon (just under 30UKP) for Christmas. Tiny, cheap and with an internal antenna. I also persuaded her to go to the local optician, and find a rigid spectacle case to keep the phone in. Magic! For under 4UKP, she found an ideal "ruggedised" container. There are not many useful mobile "accessories" for under a fiver!
The plastic cases work well, but surprisingly, the phone rang when it was called even in a metal case. No doubt the signal is severely attenuated, but if you are always in a high signal area, or not too worried about incoming calls (both of our mobiles are "emergency only"), and you want the ultimate protection, consider a metal case.
Anybody else with any useful phone tips?