(1) A six card major
This deal is from a Manchester league match recently.
At the first table South opened one club which could be a two card suit. West overcalled two diamonds to show a six card major (a treatment I have not seen before). After North passed East jumped confidently to four spades. South decided that either the opponents were making game with their big major suit fit or would misjudge over five clubs or that five clubs would be a cheap save*. West doubled and led the ace of spades, switching to the queen of hearts at trick two. Declarer won with the ace and cashed a top club followed by the ace of diamonds. West followed small without thinking, now South drew the last trump and exited with a diamond. West was endplayed, a spade gave a ruff and discard, the alternative of a heart would allow declarer to finesse the ten and play the king ditching two diamonds.
In the other room East West were less ambitious in the bidding and made declarer's life easier by starting with two rounds of spades to concede the ruff and discard immediately.
*The best saves are those that make.