
You just whack the stylus against a padded surface (for example, your palm) till it starts behaving. The technique works around 70% of the time. For the 30% of the times it doesn't, even if you are tempted to search ebay and random shady websites for replacements, grit your teeth and whack the stylus a few times more. Chances are, the beating you gave it earlier is not sufficient enough to make the errant stylus realize who is the master here.
Wacom. Whack 'em.
NB: I am really not sure how much more whacking the pen can take. Maybe I should get a replacement.
That is one of the better ones.