I'm a bit odd in that I can clutter a bit with a few items, there's paper work on my desk for example (oops, need to get that filled out for the heart hospital soon), but everything else is systematically organized to the point of being over organized. My cds are sorted by genre, alphabetically, then release date. (books, too) Even my crafts are sorted down - beads by type/size color and hue (cannot use them otherwise), fabric is even sorted specifically.
Unfortunately I can over focus on minute details of such things.

Then there's some things that I refuse to even touch: Like my DH's desk. His mess, his responsibility. I just have to selectively block it out to keep it from bothering me.