Hattrick is the original online football manager game, and it's free to play.
Current active users number 726,661 in 127 countries.
Hattrick Organizer is a popular, free, java-based helper application and is a CHPP (Certified Hattrick Product Provider)-approved program.
It's OpenSource licensed LGPL and written in Java, therefore it's OS independent.
Installers for Windows and MacOS are supplied, as well as a ZIP file for every other platform (Linux, BSD).
I am an officially recognized tester for the developers.
Submitting this request has been discussed with the developers and user community and has been met with much enthusiasm. Many of us travel frequently and would be very happy if we could include HO in our Portable Apps arsenal.
Thank you in advance for your time, attention and consideration.