I am constantly complaining about terrible battery life on my iPhone and constantly looking for ways to lengthen the amount of time I can use it in a day before a charge. My phone has been off its charger for a mere 8 hours today and I am already charging it as it had a mere 23% life left. There are articles all over the internet about how to save your battery life. Most involve crippling the device. The New York Times even recommends that you put your phone in airplane mode, effectively turning it into a media player. LifeHacker has an exhaustive guide to lengthening the life of your battery, with links to several other pages with more tips.