Examples of what can it be used for:
- Don't allow right-click on some parts of the site, or all the site
- Add an alert when opening an article
- Show a welcome message to the users
- Show some images in a modal window
- Fade in the content or the images when the page is loaded
- Process some link with an AJAX request and return the result somewhere on the page
I have had no problems with it so far - it does exactly what I wanted and I'm very pleased. No installation issues, no conflicts, etc.