[npsimons]

There are way, way, way too many ways for this to go wrong. What if you are indisposed (in the hospital, dead, etc) when it comes time to apply the patch? What if an attacker finds the security hole and exploits it before you apply the patch? And don't tell me this isn't a security hole (eg, a backdoor), because it could easily be or become one. Knowingly delivering compromised software is flat out unethical and borders on vigilantism and/or fraud. I don't condone one party failing to hold up their end of the deal when the other party has, and I don't think that "defacing" a website that someone doesn't legally own (they haven't paid for it) is wrong, but putting time bombs in software should never be done.

[koenigdavidmj]

This seems much the same as a DRM mechanism on a single-player game that requires a live network connection to phone home to the server. In either case, you have software refusing to function unless its creator gives approval. The only difference is that this is known to the player of the game.