I have an electric grinder, its a small plastic one that is powered by a 9 volt battery. It is kinda loud when it is grinding but it is pretty efficient. In just a few seconds it grinds whole buds into powder with kief accumulating quickly around the edge of the grinder. It came with my vaporizer and I mostly use it just for that but it is handy to have for other purposes as well. It's size is the main reason that I don't use it all the time. If I am grinding weed for a blunt or a couple joints it ends up being more effort than it is worth. (I have a manual metal grinder that I use mostly) It is useful and if I had a bigger one I'm sure I would like it more.