Static element?

[Helix]

Is it possible to put an object that doesn't scroll in a document? This would be useful in order to design a custom scrollbar (in conjunction with "onscroll" & "scrollBy" etc.).

[Gollum]

there is a flavour of the style 'position' called 'fixed' (supported by NS6.1 and Opera4) that positions an element relative to a point on the window - this will do exactly what you want.

For IE (and others), you will need to use absolute and use the onscroll event to reposition it every time the page scrolls.