Posted on behalf of Washte:
Birds of a feather make good dusters.
Great minds _______
Great, minds are falling from the sky and splattering on the pavement on my day off.
He who sows wind ___________________
Thank you, matt, for that beautiful bit of surrealism. 
It took me a full ten seconds to recover.
He who sows wind must take care he does not break it.
Two heads are_________
Two heads are… gonna hurt like hell if you have a hangover
“I love you not because of who you are ______________”
I love you not because of who you are, but because you’ve got so damn much money that my parents are throwing me at you.
“A bad workman ___________”
…makes a good speed bump.
“There’s a thin line between_________________”
There’s a thin line between…Quebec and New Brunswick.
Cast not your pearls…
Cast not your pearls… before casting on, otherwise your knitting will be ruined.
And continuing the almost like a proverb theme:
Oh what tangled webs we weave…
Oh what tangled webs we weave when we opt for hair extensions!
Change the name but not the letter______________
Change the name but not the letterhead when we hire a new employee.
Ours is not to reason why___________
Ours is not to reason why____ that’s why we employed Andersens, said Bernie Ebbers.
An elephant never…
An elephant never puts the toilet seat down.
To err is human, ___________________
To err is human, to um is hesitation.
Every cloud_______
Every cloud is made of millions of particles of water, all suspended in the air forming a translucent mass that occasionly accumulates so much water, precipitation occurs.
There is no honor________
There is no honorific for men specifying that they are single.
He who laughs last________
He who laughs last____ takes longest to get the joke.
The road to Hell…
The road to Hell… has been closed for major resurfacing, police advise commuters to travel via purgatory.
There is no such thing as a free_______
There is no such thing as a freemason, only Masonics and Shriners.
Do what you love and love what you’re doing…
Do what you love and love what you’re doing… unless that’s tearing kittens limb from limb.
Better to light one candle __________________________
Better to light one candle, than to attempt to juggle chainsaws in the dark.
Better to have loved and lost_______