How can I just open an Overlay (like dialog without title bar) in jQuery UI

How can I just open something similar to what I see in the th开发者_Python百科eme roller site?

Alternatively, can I open a jQuery Dialog without the title bar

You can use the option DialogClass:

$('.selector').dialog({ dialogClass: 'notitle' });

and in the CSS specify your class by removing the title ecc

.notitle .ui-dialog-titlebar {display:none}