When I'm stressed or jittery or just can't sleep, I tend to paint and repaint my nails to relax. The act of doing it centers my attention and let's me focus. Also, I know I need to avoid using my hands for at least 30 minutes.
Having done this for about two or three years, I've tried about nine hundred nail colors in every brand and formula.
Even with a collection of varying brands and shades, my all time favorite color can be found at any drug store for under $1.00 Skin Tight Denim by N.Y.C.
Its a perfect dark blue. The formula dries fast but tends to chip fast, too. I tend to spend more money on top coats than nail lacquers.
Here are more of my favorites.

Best Red-

Rimmel 60 Seconds in Rapid Ruby - $2.49 at Wal Mart
Best Red Runner Up

O.P.I. in I'm Not Really a Waitress - $8.50 at Ulta
Best Nude

Rimmel Lycra in French Rose - $2.49 at Target
Best Novelty

Best Top Coat

Sally Hanson Acrylic Top Coat - $5.00 at Wal Mart