Think, speak, and act. With age comes self-reproach: I might have done more. Therefore now do!

Qui cherche et ne saisit pas ce qui s'offre ne le reverra jamais plus.

The future depends on what you do today.

Do something instead of killing time. Because time is killing you.

Time will always exist but you will not. Stop your mind from drifting off into the future if you aren't there yet. Cherish the seconds of your life, live now not tomorrow. -Enlightened-

Well, it does make you realize that life, even at its longest, is still very short.