Some of you still think that you hv to used up your battery power to as low as possible. I start charging my phone at 60%. That way I hv a shorter waiting time. Better start charging again when you aren't using for a period of time. It won't ruin the battery.
You guys know you can use a faster charger than the included 1amp iPhone brick right? As Relentless Power said - you can use a 10w or 12w iPad brick (2.4amps) and the phone will charge significantly faster than the 1amp iphone square brick.
You are right, slow charge does prolong the battery life. That is why I start charging at about 60-70% left and I don't wait until it is all the way to 20-30%. Charging early with still high reserve batt power is not harmful, it used to be like that on the older batt technology but not anymore. I used apple's cradle and everytime I stick it in the cradle is going to charge also. And it has never hurt my overall batt life span. A small difference but not significant drop in batt life doesn't bother me at all. I changed my phone to a newer model after 3 yrs max, by that time I just sell or give the old phone to someone. Enjoy using your phone, it is just a phone.