LeerColorPicker

The LeerColorPicker is a compact and powerful color selection dialog. Its crosshair color selector (one of three ways to select a color) is based on the Hue/Saturation/Brightless(or luminescence) presentation (see http://www.nebulus.org/tutorials/2d/photoshop/color/color2.html for a discussion of these terms.), which in my opinion, makes it possible to see a wider selection of colors making it quicker to get close to the color you wish to choose. It also has some nice features such as displaying basic and/or web-safe color wells for quick color picking, the ability to choose a web-safe color close to the custom color you have selected, and easy to use retention of custom colors selected, shows hex color values if you want to use those colors in HTML pages, and more.