Here's a list of seemingly-random quotes that could apply to development. I don't recall the sources for each of these. Every now and then, it's good to have a good quote handy.
"Talk is cheap."
"Better to try and fail than to never try at all."
"If all you have is a hammer, everything looks like a nail." (good for showing how new tools can expand your thinking)
"You can be right, or you can be happy."
"Give a man a fish - feed him for a day; teach a man to fish - feed him for life."
"Consider it done." (very nice thing to say to your manager when asked to take care of a task)
"Easier said than done."
"At some point, you just need to jump into the arena."