I'll probably use it when working on my Chrono fan sequel. I already have to read about the Frozen Flame and stuff. I'll probably have to read about the Chrono Trigger/Time Egg soon to understand how they work.
The Time Egg confuses me a little. They seem to work in different ways depending on the circumstances.
Like in Chrono Trigger where it takes you back in Time and freezes the moment and where it takes you to that weird place in Radical Dreamers.
I also use the encyclopedia for the pictures, to see how stuff is supposed to look.