Need a couple of days off work? Well, how's this for a "doctor's" note?
If that's not good enough, head on over here, break a body part and print off the doctor's note and X-Ray as evidence. Don't worry, no pain is involved in the bone breaking - unless you've got some sick will to beat the crap out of someone using one finger and thus end up with an RSI in your index finger.
(Unfortunately, both probably wouldn't go down very well in the UK unless you've just got back from a trip to SA)