Refurbish your old worn Commodore 64, your old favorite keyboard, your old matrix printer or whatever old geeky stuff you have lying in your basement because it has turned yellow and ugly.. If you ever had one of the older white keyboards, an old printer or an old C64 lying around you may have noticed that the color turned grown/yellowish in time.  No matter how much you rubbed with cleaning agents the color remained, some said it was caused by smoking (but if you as I am a non smoker it seemed unlikely) others claimed sunlight. No matter what the problem was, someone now claim to have found the solution to it.  A gel “Retrobright” that can make your old device look like new once again. http://retr0bright.wikispaces.com/ You can make the gel yourself from household items; 1 pint (500ml) Hydrogen Peroxide, 10 to 15% strength (40 vol) (available from hairdressers’ supplies, e.g. the ‘Sally Beauty’ franchise in the UK) 2 heaped tablespoonfuls of Xanthan Gum (available from health food shops or online) 1 level teaspoonful of Glycerine (available from pharmacies) 1/4 teaspoonful of “Oxy” laundry booster