My toothbrush lives in a tube in my everyday bag, and like most of my stuff is also rainbow.
Now the tube is covered in acrylic paint and Mod Podge, which is basically white glue, leaving a plastic finish.
Having something looking like this got the attention from greyhound security when they searched my carry on bag. This is a thing Greyhound does now, they check carry on bags for weapons and stuff, and make everyone empty their pockets, at the occasional terminal. I got to see quite a look of surprise on the security person's face when they opened the tube and found a toothbrush.