The Bubble is similar to vaporizers you can build yourself.
It's quite simple in design and does work, but it's not the most efficient vaporizer possible.
It's best to use a candle as the heat source as it will use a lot of butane if you use a lighter.
If you rotate the glass a lot, it can be quite a good method of vaporization. It is vaporization at it's most basic, however.
If your looking for a cheap method of vaporization and don't mind a little work, the bubble could be for you!