[qiqitori]

Used <marquee> just a couple weeks ago to simulate a scrolling text screensaver for use as a video backdrop.

Actually used the linked page as a reference and laughed a bit at the "truespeed" attribute.

[keanebean86]

I use it when testing for XSS. It shows me where the dirty text is being added to the page and it can be very amusing when nested.

[ramigb]

That's an interesting use indeed, do you have any examples?