A few of my favorites, and where I learned or heard them
"Opinions are like asses...everyone has one, and most of 'em stink." - my dad
"The hardest part of any job is getting started." - my grandfather
"Do what you wanna, do what you will, just don't mess up your neighbor's thrill" - Frank Zappa (a version of "live, and let live")
"He's so stupid, he's gotta take off a shoe to count past 10." - a guy I used to work with
"He's dumber than a box of rocks." - a family friend