Whenever anyone is a speaker at an IEE workshop, they get sent a booklet of advice to help them prepare for the talk with all the usual things about not putting too much on slides, not saying too much etc. I recently received a copy which has a rather amusing error. page 5 ends, in section 1.4, with the line "... ensure that the talk is kept to the planned sequence and nothing important is left out." page 6 (or what would be page 6!) is totally blank. page 7 starts with "it is best not to draw attention to minor errors ..." and then moves into section 3.
(From the "Rest" of RHF)