There are a lot of nice JavaScript color pickers out there (colorjack, colourmod, yahoo, dojo, nogray, mootools), but none of them has a full HSB and RGB options of Photoshop’s picker. Some pickers try to generate the entire color map in JavaScript by drawing a 256×256 grid made of divs. This is very slow, which is why color pickers that go the JavaScript route often don’t draw the entire map, but instead only 4×4 or 8×8 blocks (ColorZilla).