Flash has transparent background

[NEONecd999]

You know those flash ads that are really annoying and just go right on top of the page and don't have any background color (the background is transparent)? How can I achieve that effect?

Thanks.

[Sualdam]

Take a look at these links (sorry - I hate posting links instead of direct answers, but sometimes it is best):

http://www.macromedia.com/support/flash/ts/documents/wmode.htm

http://www.macromedia.com/support/flash/ts/documents/navin_test.htm