I believe McTwist made this capability a while back, but Ephialtes failed it from RTB because it was too much of a hack to Blockland to promote. Disabling add-ons should not be an issue, in any case. It should only be enabling (and many people have made enabling possible).
However, if you have RTB you may use
this. I don't think it can enable/disable add-ons though, can it?