Beefing up iPhone security: set a PIN for shut-down to prevent thieves from powering it down to circumvent Find my iPhone

In absolutely no way can I take credit for this. This comes by way of twitter via Cabel Sasser who wrote:

When my phone was stolen in SF last year, they immediately powered it down to stop Find My iPhone. Settings idea: "Shutdown Requires PIN"?

Anyone else think this is a great idea?