Here's a fun sleepover party (or un-slumber party) game. If you already have a collection of nail polish, you have the bulk of what you'll need to make the game (and if you don't, you can pick up bottles at Dollar Tree for $1 each or buy multi-packs after Halloween and Christmas at steep discounts). If you're buying new bottles rather than digging into your personal collection, you could even give away some of the bottles as party favors.
My version of the game requires 20 different nail polish colors, but you could easily play with fewer bottles by using a six-sided die instead of a 20 sided one or using a game spinner (Brian suggested using a spinner from the game of Life and matching nail polish colors to the colors on the spinners. I've also seen several variations of this
Spin the (Nail Polish) Bottle game, which generally use 8 colors but which could be modified to use more or fewer). Also, although I thought my game board was a nice touch, you can easily make a variation of this game using only nail polish, a die, and some way of numbering your nail polish bottles.
Materials:
*20 bottles of nail polish
*20 sided die
*Painter's or masking tape
*Marker
*12x12 sheet of cardstock
*Number and letter stickers (or cutouts; I used my CAMEO for the lettering/numbering)
Directions:
*For making the game board, add a title like "Nail Polish Roulette" to the top of a 12x12 sheet of paper and then place numbers 1-20 along the board.
*Write numbers 1-20 on painter's or masking tape and stick them to the backs of the nail polish bottles.
*Place the nail polish bottles along the board at their designated spots.
Game Play
*Players sit in a circle around the game board taking turns rolling the die.
*The number a player rolls corresponds to the nail polish color a player will have to paint one of their nails.
*The game concludes when each player has painted all of their fingernails (or toenails).