I could never bring myself to rely on javascript for a design.

I'm content with what the CSS can do. I'm just worried about cross-OS compatibility, in the same way that many people worry about cross-OS compatibility when styling form controls.

I realize scrollbars aren't meant to be messed with. Part of the reason no CSS support for styling scrollbars was ever implemented is because the CSS spec doesn't assume that the user agent's default scrolling mechanism is a scrollbar. However, every major browser, ...actually every browser I'm even aware of, uses scrollbars.

Its a bit hacksy, yeah, but I think it could work. I am really hesitant though. Part of me wants to drop this idea altogether and go the more conventional route. The problem is is that its so seductively good looking.