I did this today as I locked myself out! Take a wire out of your bra and insert it in the gap between the lock and door frame, push untill you lever the door open. This only works on old chubb locks on wooden doors!

Register with the keyholding company (www.keyholding.com) They're on standby 24/7, hold a set of your keys, and will let you in within 20 mins of calling them day or night, 365 days a year. They'll also let in delivieries, contractors, plumbers etc. And they don't judge you if you're so drunk you can't find your keys - although you do have to remember a password...

Have spare keys hidden somewhere safe in your garden; don't put them somewhere obvious like under your doormat or the flowerpot in front of your door though. I also gave keys to my best friend and my boyfriend just in case.

If you've left any windows open, borrow a ladder and just climb back in - I did this last month and borrowed a ladder from a building site next door!