Mr Clean Magic Eraser! Seriously...There has been a burnt on grease spot above both pilot lights on my shitty stovetop ever since I moved in years ago. No amount of scrubbing has ever been able to completely eliminate them (and I didn't want to upgrade from the blue scrubby to the green one since there was already evidence of some enamel damage). Someone suggested I try a magic eraser and I figured what the heck...sounds like a gimmick but it might work. It seriously came off in minutes with no effort. The thing even seemed to work *better* when there was less pressure applied to it.