[Iguana]

As Big Girtha said, "Never let it turtle." I find keeping extended with a moderate stretch for long period of times really helps with flaccid length.
Especially after manual exercises. I used to stretch, jelq, and then stay wrapped with sports wrap for hours. It seemed the longer I stayed wrapped the longer it would hang lower. Some other good devices are golf weights, or an extender at mild tension. I think the key is low intensity, long sessions.