A recent piece on Yahoo had some revelaing thoughts about the cleanliness of your desk or office.

1) An organized desk says... you're dependable and timely. People with organized desks tend to be more conscientious, meaning that they are reliable people who plan well and get their work done on time. Having a messy desk isn't a bad thing (creative people often do), but others may judge you incorrectly.
2) Uncommon objects say... you're creative and open to new experiences. People with original art, unusual spaces, or a diverse array of objects are often very creative.
3) Inspirational posters and messages say... people who pepper their desks with inspirational statements are typically a bit more neurotic. If you have inspirational posters up, don't worry that they're sending the wrong message. Neurotic people are often highly successful in the workplace and the sayings they choose to display communicate their values to others.
4) An inviting space says... you're extroverted. People with especially inviting offices -- including an open door, comfortable chairs, or a candy jar -- tend to be very social.

 Okay....here's what my desk looks like.