E before O except before E-I-E-I-O. (A mixture of I before E except after C and the song Old MacDonald had a Farm, E-I-E-I-O as an explanation for the spelling of Sheos) 0925
Feed a cold, starve for pizza. Starve a pizza, eat cold feet. (Instead of Feed a cold, starve a fever.) 0501
He who laughs last laughs West. (Instead of ...best.) 0620
It's better to have loved and lost than never to have seen 'Lost in Space' at all. (Instead of ... than never to have loved at all.) 0922
It turns, therefore I am. (Instead of I think, therefore I am.) 0620
Make new thoughts, but keep the old, one is silver, and the other is old. (Instead of Make new friends, but keep the old, one is silver, and the other gold.) 0620
Mom and Dad are my relatives, therefore I am. (Combination of Einstein's theory of relativity and René Descartes' I think, therefore I am) 0322
There, but for the flippers, go I. (Instead of There, but for the grace of God, go I.) 0410
They will never buy the cow if they can get the eggs for free. (You can figure out that one yourself.) ?
Those who can - do, those who can't - do not. (Instead of ... those who can't - criticise. Or: ... those who can't - teach.) 0915
Use a condom, go to jail. (Instead of Use a condom, go to school.) 0601