Download: albook_d50_v04.icc.zip
ICC color profile in a Zip archive, 2 KB

A ColorSync profile D50 (color temperature 5000 degrees Kelvin) for the Apple PowerBook G4 with the 15" display at 1280x854 px resolution, model "January 2005".
Created with the built-in Display Calibrator Assistent (Mac OS X 10.3.9) with a lot of manual tweaking.

I have tried to compensate for the horrible pink tint of the PowerBook displays manually. The tint is not that striking at color tempertures of D65 (default) or higher, however such temperatures are not very pleasant if you need to work with true colors in artificial light, unless you're working with video.
(As a rule of thumb compare the full white of your display with a white sheet of paper: ideally the color tint should match as closely as possible.)

Installation:
Double-click the Zip archive and put the ICC profile into /Users/your_username/Library/ColorSync/Profiles/ or into /Library/ColorSync/Profiles/ (available for all users). Activate it in "System Preferences > Displays > Color", then adjust the display brightness if necessary.