Let me illustrate this with a very simple example. The user asks about how to make a simple, cross-browser AJAX request.
I answer the question with some explanation, sample code, and links to resources, should the user wish to read and learn more about the technologies and practices at his/her further disposal.
Is it acceptable in this situation to recommend my say, lightweight AJAX library, with a link to its homepage? Again, as part of a detailed, well thought-out answer.
The reason for promoting this example library is not to obtain revenue or visitors, but to express a biased opinion, stating the usefulness of said example library.
