MacBook owners that are getting bored of the stock look can easily make a few modifications to it to spruce up its appearance. As seen in in the guy's flickr page, he's added a See-Through Speck Shell, a custom rainbow Apple logo, an 802.11n card from a Mac Pro, and black MacBook keys as seen in the Zebra MacBook.
Nothing extraordinary, but it goes to show you can customize your setup with not too much cash. We're probably going to grab one in a few months for our lady friends, so this guide should be useful for us since we don't have the time or the patience to go hardcore and put the guts of it inside, say, a completely different shell.
Speck Shell [Speck]