Always be prepared to give an answer to everyone who asks you to give the reason for the hope that you have. (I Pet. 3:15, NIV)
It's actually only part of the verse, and the rest of the passage is almost always left out. You'll see why in a second. This "give an answer" command is obviously used by pop apologists and creationists to explain why it's important for us to have an answer for every criticism that comes along. Typically I see the same folks literally answering every little insult that comes along, and unfortunately, they often stoop to the same kinds of insults themselves.
First, let's just dissect the verse they cite. What is the reason for my hope? My hope is Christ crucified and risen. I have hope because I'm a sinner saved by grace. That's my whole reason. It's not because I can refute evolution (I can't) or because I can prove the Flood (I can't) or because I can make evolutionists look silly (I don't).
Now look at the rest of the passage in I Peter 3:8-17. Verse 8 begins with "live in harmony with one another" and verse 9 says very, very clearly, "Do not repay evil with evil or insult with insult, but with blessing, because to this you were called so that you may inherit a blessing." Look at verses 10-11, "For, Whoever would love life and see good days must keep his tongue from evil and his lips from deceitful speech. He must turn from evil and do good; he must seek peace and pursue it." Verse 14: "even if you should suffer for what is right, you are blessed." When you answer for your hope, "do this with gentleness and respect, keeping a clear conscience, so that those who speak maliciously against your good behavior in Christ may be ashamed of their slander. It is better, if it is God's will, to suffer for doing good than for doing evil" (I Pet. 3:15-17).
Now that's interesting. In Biblical studies, the term eisegesis refers to the bad habit of reading meaning into a passage instead of drawing the meaning out (called exegesis). Exegetically, I Peter 3 seems to be telling us to endure the insults of mockers graciously and gratefully, knowing that it is better to suffer for doing good than evil. When they demand an answer, tell them the truth, "For Christ died for sins once for all, the righteous for the unrighteous, to bring you to God" (I Peter 3:18). God will bless you for your faith, and that's a better reward than anything else I can think of.