Hide Your HTML Source
Sometimes you might not want to allow guests to your website to view the HTML source code. You can disable the right click context menu by using the following bit of code in your page:
<body oncontextmenu='return false;'>
You can use this feature to prevent users from right clicking and saving an image from your site. This is support by IE and Firefox. I have seen sites use similar functionality to this to pop up an alert with a copyright message is a user tries to right click on an image.