I don't even use a cell phone, and just started experiencing this last week. I was in a large store with my mother, and thought the store had some giant air compressor running; asked my mother if she could feel it. No, she says. Then, we're in another store and I felt it again! Off and on for the past 4 days. It feels as though I am standing on top of a large piece of machinery! I am fairly active, and had back surgery about 8 years ago to clean around lowest disc; I have had leg cramps/spasms occasionally since then. The vibration is extremely distinct. It doesn't really bother me, it doesn't hurt -- it is just puzzling. Be interesting to find a definitive answer to this!
maybe your pinching a nerve while standing somehow or even constricting blood flow somehow, ask your doctor.
