I just got a new show-off lapto ... well, 5 kg brick with graphics, and featured is a 18.4" 1080p LED display. The display really is brilliant for a laptop and deserves the finest in desktop layouts.

Yeah, I know how to google for "desktop windows nice and cool". But I'm wondering if anybody know of more specialized sites where I can browse by category, maybe get interactive and / or animated backgrounds, maybe there's a program that changes backgrounds randomly from a choosen set, etc. etc.

Oh, and a cool CPU meter, and perhaps some stats overlay stuff, and perhaps a sleek RSS reader somewhere down in the corner, oh, and ... you get the picture.

In short; I need input on proper desktop customization. OS is Win7 Home Premium.

http://rainmeter.net/RainCMS/

I've never used Rainmeter myself, but it's something that I've frequently seen come up for questions like this.

Also, Win7 allows slideshow wallpapers.

Win7 can do that, just check the Personalize settings :) and for this I use Rainmeter
http://rainmeter.net/RainCMS/
You can get some seriously advanced stuff out of Rainmeter, but the default instalation has all the basics too. Along with a nice pdf tutorial on how to set everything up :) This is how my desktop looked after just a bit of tinkering :)
http://dl.dropbox.com/u/2489255/Desktops/rainmeter4.jpg

edit: ninja'd :(

If you don't mind messing around a bit with the Windows files, go through Deviant Art for Icons, custom themes, and custom start orbs.
http://browse.deviantart.com/customization/skins/windows7/visualstyle/?loggedin=1

There's also Stardock's Object Desktop which comes with a whole suite of software if you don't mind paying.
http://www.stardock.com/products/odnt/
http://www.wincustomize.com/explore/

If you want a bunch of gorgeous wallpapers go to: http://interfacelift.com/

As far as things like meters, Rainmeter is popular, but can take time to set it up the way you want. I personally just go with Win7 gadgets as they're good enough.

Actually I always thought Stardock's Object Dock and Fences were both very slick looking. For some reason I never tried out Windows Blinds from them. Being able to make your desktop disappear save the background and Object Dock launcher was super slick, to me.

EDIT: Re-reading your post it almost looks like you'd be aiming at some desktop widgets of some kind.

With Windows 7 desktop wallpaper rotation is built in; simply select a folder rather than an individual image and you can choose how often to rotate, whether to do it in a fixed sequence or randomly, and so forth.

Yeah, I use this, and have selected my photography to be slideshowed. Works beautifully.