As in...

"Some toolbar buttons are greyed out and not clickable"

...any comments on this usage? Is it 'fine' as a verbal phrase and as the adjective 'greyed-out'? I assume it is fairly new and only used in computing circles.

And a useless bit of information on the gray/grey topic:

In HTML and CSS all grays are named somethinggray except lightgrey.

http://en.wikipedia.org/wiki/Gray_(color)