Use a bobby pin to make polka dots on your nails. You have to bend the bobby pin apart in order for it to work but after that it's the best thing ever for making polka dots! I did it for my birthday last year!
DIY Glow in the Dark Nails. Pour the contents of a flow stick into some clear nail polish, paint your nails a bright colour and top it off with the glowing top coat. The effect will probably be temporary since glow sticks tend to fade rather quickly.