ColorJack provides great tools for picking and coordinating colours. The tools include:
* Color Galaxy - online colour library visualizer
* Color Sphere - visualize colour theory. It also comes in widget form
* DHTML Color Picker - pick colours in fine detail
* Color Matrix Library - colour functions - hue, saturation etc.
* Color Blindness Library - color blind simulation
* Color Conversion Library - convert to/from various colour formats
And as if that was not enough ColorJack have also created Sketchpad - a drawing application including the following tools: text, shape, spirograph, brush, calligraphy, pencil, paint-bucket and stamp.
Colors, gradients, and patterns as well as some generic drawing utilities (marquee, crop, eraser and a HSL/RGBA Color-Picker) are also included.
ColorJack could be useful for many different subject areas including web design, graphic design, art, mathematics, physics...... etc.
Patricia Donaghy is an ICT Teacher in Dublin, Ireland. You can read some more information 
