I've been having fun this summer making decals out of flexible filaments. See Dragons for Everyone and Flower, Butterfly and Bee Decals.
I have also included thick versions for those who want to print in PLA or other filament. I think either version could also be used as a badge and pinned to a hat or jacket.
Clean your build plate well before printing the thin versions. Wet the smooth side and apply to a clean window, mirror or other smooth wall. I have found sometimes they don't always stick and then you might have to use a piece of tape or thumb tack. That said most of the stickers I have printed have stuck.
3d printing enthusiast specializing in flexible prints. Check out my flexible designs here on this site and my posts on Instagram and Twitter.