This glass siphon brews a smooth, strong cup of coffee with little to no bitterness. I started using one recently and right away the taste was just awesome. It’s really an excellent, efficient brewing method, provided you want to get involved. You put the water in the bottom “globe” and coffee grounds in the top, then put the bottom unit on the stove with a medium flame. Once the water begins to boil, you place the top globe onto the bottom one, which allows the water to travel into the top chamber to begin brewing the coffee. You give the coffee a quick stir, cover the top with the lid and after maybe a minute, take the whole unit off the burner. As it cools, the coffee is siphoned back down into the bottom through a cloth filter, which helps extract most of the moisture and flavor from the grinds via a natural vacuum effect, rather than the force of a standard French press (step-by-step photos are available at Stumptown’s site — click on the link to “brewing guide”). You can also see vac pots in use at the Blue Bottle location near the Chronicle building in San Francisco. The $20,000 system they have there is just a fancy vac pot. While researching a coffee maker called the Clover, I went from addict to obsessive, so in addition to the vac pot, now I kind of want a Chemex and I definitely want a Burr grinder; once you notice the difference in taste, it’s easy to get sucked in. Personally, I love this method. If you spend money on good beans, it’s well worth the extra effort to brew a cup that tastes that much better.
Here's a video of the final siphon process.