(1) Leicester City vs Nottingham Forest (Carling Cup Tie)
Leicester City (18 Sep 2007) sportingly allowed Nottingham Forest a free goal in appreciation for their willingness to abandon the previous game (Forest were leading 1-0) so that they can attend to a Leicester player who suffered a heart failure. Technically, Forest do not need to abandon the previous game. Moreover, in a replay, the score will be reset to 0-0. Hence in appreciation to Forest's willingness, Leicester granted them a free goal, informing them only 20 minutes before the game! Read more about it here and here.
(2) West Ham vs Everton (Premier League)
Paolo Di Canio (Dec 2000), upon seeing the opponent's goalkeeper down and injured, decided to catch the ball with his hands despite a golden scoring opportunity to level his team. He received a fair-play award for his sporting gesture.
Cheers to good sportsmanship.