I've worked in the tech industry for nearly 20 years now, and I've seen some pretty dirty equipment. From smudges and smears on the screen to cookie crumbs and fingernail clippings in the keyboard. Nasty stuff. My philosophy: if you truly care about taking care of your technology (a.k.a.: financial investment), it should show in how clean it is physically. There are two products that I use on a regular basis to keep my tech looking like brand new (which, by the way, helps tremendously when it comes time to resell it to someone else so that you can upgrade to the latest and greatest model):
Monster iClean
I've tried a lot of different screen cleaners, and this is the best I've seen. The cleaning solution is an alcohol-free, ammonia-free solution that safely removes dust, dirt and fingerprints from computer and other electronics (cameras, mobile devices, etc.) screens and displays. It also features a special polymer to help protect surfaces. The kit includes a MicroFiber cloth to prevent scratching.
Compressed Air Can
I really don't have an allegiance to a specific brand on this one... any brand will do (air is air, after all). The point is, I use it. And you should too. Electronics attract dust like a magnet attracts metal. A weekly air spray of your electronics (especially around fans and intake/exhaust areas) will not only help to keep your tech looking good, but will improve the longevity of the device by keeping it dust-free.
