Flashing warning lights?
 

Is this possible to modify your health bar, so that when you reach near death (red) the bar will do a continous color warning flash at you until your health gets higher?

Gawd how many times have i died because being an idiot, i dont pay attention to the HP bar when im looking at the 10,000 other icons/commands i need to do? :D

Not possible directly... What you could do is have a flashing image that sits under a portion of the health bar so it's only visible when you get below a certain amount, but you'd probably only be able to see a few pixels of it before you're dead.