I Have to Agree with
EtherealRemnant on this but I want to also add that constantly charging the phone can hurt the battery as well. When I first got my Touch last year, I always had it plugged to the wall at home, work and even the car charger. never let the battery go down more than 50% for months and when I actually started using the phone without the constant charging the battery would die out after just a few hours as if the battery got addicted to the all day charge.
But that's just my experience.