Re: I called the cops
I've seen it done, and was there when the police arrived.
Of course even if you stay on the line to explain your innocent mistake, the police in the US are obliged to turn up at the registered premises for the phone number. They need to check all is well.
A lot of private office exchanges are configured to forward "911" from an internal phone to the police, as if you were on a normal landline. There is even a US Patent for it - US20040081290A1.
Some interesting snippets in this Cisco manual:
"If the caller hangs up before talking to a 911 dispatcher, then emergency services will be sent to the site to verify the emergency. Since most of these accidental calls are caused by users misdialing the number or by accidentally entering the long distance access code twice"
"Since many dialplans are based on an access code of 9 followed by a long distance number of 1 or 011 for international calls, accidental calls to 911 happen on a frequent basis."
So remember when you are next allowed into the States and want to call home in UK:
9 - "oh!!" - 11 - 44 - number without the leading zero