There is a product I've seen floating around called "Cyber Clean", which essentially is some kind of special goo that can get into the groves of your keyboard and clean out all of the dirt.

The process seems simple enough, as documented on the site:
- Remove the compound from its packaging and knead it for about 10 seconds. This allows the compound to adapt to the pH value of your skin. Use only with dry hands.
- Place the compound on to the surface you wish to clean and press firmly to allow Cyber Clean to enter into all gaps and crevices.
- Pull the compound out. Dirt and bacteria are trapped inside the membrane system. Repeat cleaning action if necessary.
- Put the compound back into its re-sealable packaging and close it carefully to ensure the compound remains fresh. Store the product in a cool and dry place, away from direct sunlight.
Your other viable option is using compressed air, which you can buy in a can, to clean the dust away.
