Hot Topic has the perfect nail polish for Halloween with Blackheart Beauty Skull Nail Polish. I picked up 4 shades including Dark Purple Galaxy, Hot Pink/Black Splatter, Green AB Iridescent and Pale Pink Shimmer.
I tried all 4 on one hand and I like the Dark Purple Galaxy and Green AB Iridescent the best. All 4 shades are nice but Hot Pink/Black Splatter and Pale Pink Shimmer are a bit on the light side.
All of these shades would be great for witch or wizard costumes and the skull bottle is really cool. They are made in the USA.
They also have a ton of shades available including: Blue, Pink & White Splatter, Violet & Blue Glitter and Hit Pink Matte.