I dread to ask but...marquees?

[LeadMagnet]

You can use the setInterval() command in javascript to increment the position of the text from the left of the screen. Set some conditional statements for the width, should work i think. Would need some tweaking to properly determine what happens when it reaches the right-hand side, but shouldn't be too hard to work something out.

[philjohns]

Sounds like what I need - you couldnt give me a link to a tutorial could you? ;)

[LeadMagnet]

I don't know of any... just thinking off the top of my head.
Look up how to use setinterval()
you'll need to use something like document.getElementById('thetext').style.left+=5;
Or something similar. That should get you started.
it'll need to be a relative or absolutely positioned container.