Vlad

From what I can see it this thread, your work on either a book or a builder has to be seen as a labour of love.

It appears that many programmers will get your knowledge for free by asking questions in this forum or reading your articles.

If you charge $60 for your book or $30 for your grid builder, you may find the enthusiasm drying up because many programmers are used to getting their help for free. Or they may have figured out their own solution by the time you go to print.

Anyway, people who write books and tools are a breed apart, so you will have your own way of deciding what you should do.

Mike Smith