I've started planning a comprehensive e-book on the Grails Resources plugin. The plan is that if there is enough interest for this to be financially viable, I can begin bashing this out in January 2013 and it shouldn't take me too long to complete.
I'm using Leanpub.com to do this, so that I can gauge interest before I actually start writing.
To get more details and register your interest and how much you would consider paying, please visit the Leanpub page.
If there is insufficient interest I am unlikely to write the book, so this will be another intriguing experiment into the viability of ongoing unpaid open source development.
Let's hope it goes better than support subscriptions!