Well, we've all tried submitting nicknames to the site name rater time and time again. Most of them come back with witty insults. So I was looking through the archives of the names rated and some of them were really funny. Here, you can post your favorite ones from him (please note that you can't take credit for these unless you are the name rater, and why would you tell us that. All credit for insults go to the name rater.)
From the Johto name rater:
You couldn't solve a completed rubix cube.