If keyboard is warrantied call the service (it will probably get you a new keyboard, or fix it) if warranty expired ... i dont know, get a new one (at least thats what i do)

Buy some of my Famous Keyboard Grease, just $49.95. Please just email me with your credit card number. Really. Trust me it works.

Disassemble your keyboard with a screwdriver and clean inside from dust and grease with any plastic cleaner. But the best way is to buy a new one. Why bother if it's cost almost pennies?

Cleaning a keyboard is a difficult and time consuming thing. Many times I've found that replacement is preferable to fixing it. If you can't afford to replace it or are emotionally attached to this keyboard then here's what you do. Get a bottle of isopropyl alcohol, a one inch paint brush, a can of air and a clean lint free cloth. Find a clean flat surface preferably wood (or other non-conductive surface). Place the un-plugged keyboard on the surface. Slowly and carefully remove the thousand or so screws on the back of the keyboard (more like 12-24, but it will seem like far too many). As you slowly take out the parts, watch that any springs (on older keyboards) don't go flying off the table. If they do, my experience says they'll probably be just out of reach under the 'fridge. Newer keyboards use molded rubber tubes to give you your bounce-back. As you remove the circuit board(s) blow the loose particles of food and dust off with the canned air. Lay out all the pieces in the order they are removed to facilitate replacement. Gently remove clean with isopropyl and cloth the actual keys and place down in order (you want them to go back the same way they came off. Once the keyboard is free of keys take your one inch brush (which you have prepared by cutting all the bristles to a one inch length). And scrub the keyboard clean with isopropyl. Blow off any loose matter. Once it has all dried (it won't take long), reassemble the keyboard carefully cleaning any remaining particles with brush and alcohol as you go. Once the keyboard is reassembled play with it for a few minutes, shake it a bit and give it one last blow with the canned air. Let it sit for twenty minutes and then plug it in. So you can see how after all that most guys will just go to their local geek store and pay $12 for a new one. Hope this helps.