A fixed-width CSS-driven Drupal theme that doesn't suck. In its author's opinion.
This theme builds upon Bluemarine, adding only those additional styles and changes required to make the leap from one to the other.
I hope it can serve as an example of how to make seemingly-radical theme alterations while (in this case) actually only altering about 40 lines of code.
See a real-live web page with it here.