ColorWheelFree
Color Wheel is an application to help people (programmers, designers, etc...) find sets of colors that work well together. Choose between Complimentary, Analogous, Triadic, Split-Complimentary, Tetradic, and Square color schemes. Adjust the tint / shade and transparency of the color. Once you have a set (palette) that you like, share it (Twitter, Facebook, email, copy to pasteboard, etc...)