Templates for “notes-examples-… environment”

Question

Books often use special environments to display examples, theoretical details, notes, etc. Here is one example:

Do you know any website that collects templates for this kind of special environments (something similar to "beamer theme gallery" but for "notes environments")?

Answer 1

I don't know of any website that collects templates of theorem-like environments. But see the manuals of mdframed and the ntheorem packages for examples. You can also search this site for examples of the use of these packages. Here are lists for mdframed and ntheorem.