I have updated the appearance of my personal blog, which you can see here:
From my old design, I kept the header image (because you know, robots), and the menu gradients, which I copied from Kim's site (http://www.nÃ¸rrebo.dk/) and changed the colors using the gradient editor from ColorZilla (http://www.colorzilla.com/gradient-editor/).
I also kept my old background image, but lightened it up a lot.
I added a box shadow to each post and widget area, and a bit of a radius to each border, so they (kind of) float above the background. (I may play around with this some more.)
I changed the format of the sticky posts from having a colored background to having a different color box shadow.
I also use Prasanna's code to change the appearance of the the "Previous" and "Next" links. You can see how he accomplished this on his blog here: http://www.prasannasp.net/tweaking-previous-and-next-post-links-in-graphene-theme/ (Thanks, Prasanna!)
Big change #1: I used the Ubuntu font for everything. I didn't install it as a webfont, so if you don't have it installed, you'll just see everything in a sans-serif font. So I may may change that later.
Big change #2: I used the vertical effect in the slider, as I had never seen anyone use it before. It's pretty cool.
As always, feel free to look at the source code and borrow/adapt/steal. Enjoy!