Switch the M and the N key. Simple, but hideously effective 

I had a cop pull me over the other night and he asked me if I had been drinking to which I honestly answered yes Officer I've had atleast four drinks in the last 2 hours 

he then asks me to blow into the alcohol detection device which I did and no alcohol was registered he removed the straw and asked if I could do it again and I did same result he then asks me to wait there so I did quietly chuckling to myself while he radios up his Sargent to come do the same test 

The Sargent arrive has a quick talk to the other officer then come to my window and ask me if I had been drinking to which I gave the same reply as before Yes I have had atleast 4 drinks in the last 2 hours he asks me to the blow in the straw and I do and same result zero alcohol registered he then asks me what I had been drinking so I said 4 cups of coffee he burst out laughing but the other cop was not amused I said to him next time you might want to ask if someone has been drinking Alcohol and not just drinking it also helped me out as I knew the Sargent and had spoken to him whilst working on a bar door early that night so we were both having a good laugh at the expense of the first cop  

joker97: You are brave

meh not really I know most of the cops round HB as I'm a security guard so deal with them quite often I hadn't seen this one before though so thought he must be a newbie lets see what he does and sure enough silly mistake of not being accurate when you ask a question will get ya pranked  

Athlonite:

 

whilst working on a bar door 

 

Hah! Yet another IT guy who also does door work :-P Seems to be a surprisingly large number of us around.