Sticks and stones might break your bones, but a little colored blade can hurt even more. Just because a knife has many functions to perform, that doesn't mean being classy and fun can't be it. People have a real liking for blades because they are multi-functional and dangerous-looking. But now the badass image around knives is expanding to include all tastes for knife collectors. A rainbow knife is the new weapon kid on the block that’s growing in popularity.