Metallic Nail Polishes like this can be used for custom components in your model

Tip for March 2004:
Overlooked Paint Sources

Model paints don't always have to come from the hobby store. A frequently overlooked but excellent source of custom colors is nail polish. Polishes can be brushed or airbrushed, and range from metallics to traditional hot rod colors to pearlescent and color-changing paints. For custom action figures, nail polish can also be more resistant to damage than regular hobby paints. Like all paints, though, make sure you test the color in an inconspicuous area first.