Sometimes if Sphero's battery runs uber low, then when you put him on the charger he will flash a blue/green/teal color.
To get him out of his party state, we need to put him into deep sleep, give him a jump start, and then let him rest for a while.
While he is flashing in his charger, run as high powered of a magnet as you have around his circumference (imagine he is a planet and you are running it around his equator).
This should stop the strobing.
Let him sit in his charger for about an hour and then pull him out and shake him awake. He will probably be flashing red(low battery).
Now place him back in his charger for a couple of hours and he should be back and ready to roll.
To prevent running into this issue again, it is very helpful to keep Sphero on the charger and plugged in while not in use. That way Sphero is ready to roll whenever you are.
Watch the video: http://youtu.be/ah5G9_pJuYo