Maybe it's just me, but I'm really paranoid about my phone running down during the day so the last thing I do before I jump into bed is to . . . plug the phone up to charge for the night.
And, as a precaution, if I should run low during the day (and it depends on how much I'm using it during the day to get hold of vendor reps and such) I'll have my cable in my purse so if it needs a quick charge, I can plug into the spare outlet behind my desk (after unplugging the ocillating fan that does NOT help in the backroom when it's 90 degrees outside).
I guess I'm just weird that way.