Any resemblance to a <marquee> is purely coincidental
There's a choice of 7 individual colours (or the nifty rainbow option, pictured below), motion blur, and a few tweakable options to play around with. It doesn't work in Internet Explorer (it's only designed as a proof-of-concept, not as production code), but anything that supports CSS opacity (Firefox, Safari and Opera on Windows) should work just fine - Safari's rendering engine seems particularly nippy.
Extract the .ZIP archive somewhere and open the scroller.html file in your browser - everything should work fine there. You can edit the HTML file to tweak the various settings - if performance is an issue try setting blurLevel to 0.