A few quick thoughts to answer your post:
* "You see a glass that's half-full; I see a glass that's half-empty."
* "It's six of one and a half-dozen of another"
* "I see roses and you see thorns."
* "You say 'tomato', I say 'to-mah-to'." (long a sound in the first tomato and short a sound in the second)
* "If I said the sky is blue, you'd say it is yellow."
* "One man's trash is another man's treasure."