整理自Color picker utility (color pipette) in Ubuntu

GPick:

sudo apt-get install gpick

It's got a lot more features than gcolor2 but is still extremely simple to use - click on one of the hex swatches,move your mouse around the screen over the colours you want to pick,then press the space bar to add to your swatch list.

It also has a traditional colour picker (like gcolor2) in the bottom right-hand corner of the window to allow you to pick individual colours with magnification.