I've got good news, and I've got great news.
The good news: There's a DreamWorks-themed gallery on deviantART that's now accepting Croods-related fan art.
The great news: Thus far, there's only ONE submission.
You know what that means, don't you? No matter WHAT you give them at this point, they're bound to post it out of sheer desperation.
Want to submit a pencil sketch of a stick-man holding a stick-club? Do it. You're automatically the SECOND BEST artist in the Croods folder! I hope you've emptied your email inbox recently, cuz the hyperbolic, emoticon-heavy comments are gonna pile up fast.
Tempted to trace your hand with a crayon, then flip the paper upside down, adding just enough blue and green scribbles to justify labeling it as the saber-toothed tiger from The Croods? Get to it! Writer/director Chris Sanders is on deviantART, and there's a slim to nil chance that he'll happen upon your work and DEMAND that DreamWorks send the company jet to pick you up so that he can make you a STAR in the multibazillion dollar a year animation field. (Tip: You may want to specify 'window' or 'aisle' seat somewhere in your drawing. Do it subtly, though. Sorta like how Al Hirschfeld used to hide his daughter Nina's name in all of his caricatures.)
Think about it. Being the second person EVER to contribute to the Croods folder is a ONCE IN A LIFETIME OPPORTUNITY. (Although, technically, so is being the third, fourth or fifteenth. But no matter.) This must be how Jeffrey Katzenberg felt when he boldly stepped forward as the second guy in Hollywood to green-light a CGI flick about insects. Don't you want to breathe that same rarefied air? Then submit yer masterpiece here.
I'll be posting mine on Friday.