wouldn't it be good?
Not GPS, 3.5G, camera etc...
It is a build in battery!!!
This build in battery can last you for 5 to 10 mins, which enough time for you to change the battery. While changing battery, someone else who call you can get you too. Just in case the other party got last chance to call, right? (Touch wood)
I wondering why all keep on designing slim, high MP camera phone and no one willing to have a build in battery for standby? If got this feature, I think can save a lot of ppl, esp when u forget to charge n w/o a extra batt with u plus you need to make an emergency CALL!!!