javascript preloader?

[runnerunner]

I'm looking for a preloader like the one found here:
http://www.net-games.biz/funny-games/Sift-Heads-4.html

It looks like he uses div tags to show or hide either the advertisement or the flash game. After the preload bar loads completely then it hides the progress bar and advertisement, then shows the flash game.

I think it's done using javascript, but I don't know enough about javascript programming to be able to follow how it works. Does anyone have any ideas?

[dimitar christoff]

no. it's flash. a js preloader is also quite doable.

for example, i did one a while back for a lightweight image gallery that i have yet to complete (the gallery, not the preloader - it works fine):
http://dci.uk.net/gallery/

it loads images as thumbs, medium and large views. The user does not need to see what his bandwith is being used on but i like it :D
it's reliant on an array of assets (images) that are being loaded sequentially with the % bars being updated after the onload event from each one.

also, uses mootools 1.2.1 with a custom fix for Scroll.js - but the preload code is there.

if you're after something less complex, google 'javascript preloader' i bet you get 1000s of hits!