My favourite KB is 10-15 years old, an electromechanical Acer of generous size with the three keypads, alpha, positioning and numeric. It's getting a bit geriatric now, though, and although only one shift key and the space bar are prone to sticking down, some of the other keys are occasionally a bit slow to return, so that I produce more typos than I used to.
Is there any way I can lube or otherwise service it? Preferably risk-free.