Well, not exactly clown bikes, but Specialized is creating quite a few brand new "revolutionary" bikes. Check out the link to see all eight of these monsters. Supposedly they revolutionize the aerodynamics while biking, but I m sure that can be done just as easily without making the bikes look like the Toxic Avenger's mutated dog, Squirt.
Revolutionary Venom Line Being Developed by Specialized [Mountain Bike Tales]
Edit: We got punk'd straight up Ashton Kutcher Style. Loof Lirpa Publishing posted these bikes. And the convenient dyslexic reader noticed that Loof Lirpa is of course April Fool backwards. At least we didnt spend hours rendering odd looking bikes for a joke. So there!
UPDATE - We didn't get punked. After the jump.
The bikes were taken from concept artist Scott Robertson, who has a step-by-step tutorial on the technique used for these renderings.
They weren't created with the intention of being "April Fools" jokes, but
apparently someone else thought they would work well as such.
I guess it should stand as a testament to how talented the guy is...