For those who want to listen to the 80's musical version of the name just youtube search thunderchild.
For myself I was trying to think of something that sounded cool and I thought of war of the worlds.
The 1 in chi1d came because thunderchild is semi-common? I have about a 40% chance of getting it. Anyway I just got used to typing in the 1 instead of L.
For those who are not a fan of 80's music the story (abridged) goes as follows. Aliens Invade, A passenger ship is leaving to avoid the aliens. Aliens go to block passenger ship. The Thunderchild is a iron clad ship that gives it's last full measure of devotion to help the passenger ship escape.
Why not, besides I have also always liked to be outside in thunder storms, something both exciting and calming about them at the same time.