Color Scroll is a very simple utility that came with the Spectrocam photospectrometer software.
It's the quickest way to see which colour is produced or represented by a 3-digit colour coordinate - e.g. 201 110 187 (RGB).
Great for either visualizing colours or discovering which values are required to produce a certain colour.
Of course, the same thing can be done in Photoshop or any other number of progs, but this quick little utility starts instantly and can be maximized to fill the screen.
Download link is in my Spectrocam 2.05.5 [Portable] post:
Download the Spectrocam software and run "Colscrol.exe".
You can enter colour values for RGB manually, or just play with the sliders until you see something you like!