Thanks for all the replies!!
Thanks for the replies except the harsh ones about me having a drug problem and not using my brain.... Ouch that hurt!! The truth is i suffer from really bad anxiety at that sort of stuff and i hate public speaking but i had to get up and tell a few jokes (had no choice) so i needed something to help me relax. Anyway the jokes went down a treat andnNo-one suspected anything even though i gave my food away to a good friend of mine (who is a full on anti-drug christian!!)
By the way in case anyone is curious it was a sort of a work dinner. It was our yearly army dining in night!!