Desktop and Theme customization

A few questions...

One of the things I love so much about Mac OS X is the options as far as customization goes. I have already done several things regarding customizing my computer, but I was curious about a few others.

Is there a way to change the opacity on the dock? On Windows you use to be able to download an identical mac dock for your desktop, and there was this feature which allowed you to change the opacity.

I downloaded a black desktop background, and I wanted my dock to blend in nicely. In addition, I was curious about themes for Mac OS? Again, Windows, there was this program called WindowsBlinds. It was a cool program, but killed your system resources. That's why I never got into it. But on Mac, is there a way I can download themes? I don't really want themes that much. It's more that since I have a black desktop, I'd like the top toolbar (or whatever you call it) to be black or a different color to look better.

This is all aesthetics I know, but it's fun

Cleardock for the dock and shapeshifter for the themes. For Shapeshifter It will make some apps not work but if you open terminal and type "sudo killall translated" without the quotes it should fix most of the problems.
http://macupdate.com/info.php/id/8808
http://www.unsanity.org/archives/2006_09.php

what about downloading a theme from interfacelift?

You need shapeshifter to apply the theme. Thats what all those themes on that site are for. Your gonna have to pay for shapeshifter if you want some sweet themes.

What do you say, do you think it's worth purchasing?

Also, on their website it says that shapeshifter is not compatable with intel-based macs. Does this mean that it is not compatable at all, or that it runs under Rosetta since they haven't released a UB version of the program yet?

It worked fine on my intel mac. I'd give it a try, I only did the trial and didn't purchase because I'm not a huge fan of skinning and Aqua looks fine to me, but it worked great when I had it.

Two more apps you might want to check out are Candybar and Afloat. Candybar lets you change icons and Afloat lets you change the opacity of windows (cocoa based apps only.) Afloat is free but Candybar costs around $20.

I would pick up shapeshifter if you like the way it works. I purchased it even though its still in beta. Im sure they will fix all the minor issues before long.

I'm positive though on their site it says that shapeshifter is not intel mac compatable. I trust you and everything, but I just want to be positive before I blow twenty bucks on it.