I haven't had this problem yet with my Climax Twist, but I'm super careful with charging it (to the extent of setting an alarm for it on my cellphone). There is no indicator for when the Twist is fully charged, so how do we know to stop charging it without setting a timer?

And to Dangerous Lily-- I assume that you unplugged it from the charger before trying to turn it on? I recall trying to turn it on once while it was charging and it didn't work. I've always noticed warmth from the middle while it was charging, too. If you're talking about it getting warm and non-vibratey even when unplugged (which is what it sounded like), though, then yeah, that's a bummer.