Here is a mug I made for a friend (though by size, it's almost a bowl ). This is a 99 cent thrift store mug that I fancied up with a black sharpie and some enamel paint, and baked in the oven to seal it. I've tried just sharpies in the past, and found the colors faded too much for my liking. The paint works fairly well though!
Thanks for looking!