Modal Dialogs
These are only supported by Internet explorer, so tend not to appear all that often. They contain html, but need to be accessed in a certain way.
The following html would open google in a modal dialog.
window.showModalDialog('www.google.com')
The following dialog was created using the script on http://msdn2.microsoft.com/en-us/library/ms536759.aspx
Note the title of the window - Web Page Dialog - this is a way of determing if you are dealing with a modal dialog or a regular browser window. With a modal dialog, you wont be able to give focus to your main browser window.
