This is a fairly topical post after the All Blacks' impressive win last night to secure back-to-back world cup titles.
When I was teaching in NZ I was alwyas looking for different ways of getting mechanistic concepts across. Being an Australian in NZ, and a fan of rugby I used the slide below to revise the difference between SN1 and SN2 reations at the start of the second year course. The ball was the leaving group, the guy holding the ball is the electrophile and the tackler was the nucelophile. It usually went down pretty well and got a laugh...even the subtle jibe of the the Kiwis doing the late tackle.