Many people know about the relatively recent popularization of a brewing technique that's been around for a while, even in the United States--manual drip. More shops are brewing by the cup using the Hario V60, Beehouse drippers, or Abid drippers (a hybrid immersion/drip method). These shops do not frequently feature cloth drip because in a cafe environment, the logistics are difficult to work out. Even Blue Bottle, which has done more to popularize Japanese manual techniques than any other shop, only offers cloth drip as a special (also known as nel/flannel drip, or sometimes Woodneck--in reference to the Hario model).
Cloth, of course, requires more work than paper. One needs to rinse the filter thoroughly after use and keep it wet or submerged in the fridge in between uses. What's the benefit?
I think of cloth drip as clean French Press. While I appreciate the sheer bodaciousness of a good Press, I don't appreciate the sediment. Flannel filters let through a good amount of oils and insolubles while keeping that grit out. In case you're wondering what the difference is between Nel and vacuum pot--which can also take a cloth filter--the former has a much denser body (since more coffee is in contact with the filter) but less flavor clarity and less aroma (for temperature reasons).
There is also an environmental benefit. A cared-for cloth filter can last several months and is more sustainable than paper filters are.
They are also, incidentally, not processed using potentially health-threatening agents, as paper filters sometimes are. At the same time, however, some people believe that the coffee oils that cloth or metal filters let through can raise cholesterol levels; whether one should be all that concerned about cholesterol is an interesting question...but that's beyond the scope of this blog!
Yama and Hario both offer cloth-drip brewers. ROASTe stocks the Yama version. The difference between the two is mainly aesthetic (footnote: the difference between Yama and Hario vacuum pots are much more significant...the latter offers more control). Hario uses higher-quality glass and has a wood-and-leather handle around the brewer's neck and the nel filter itself is held by a wood-handled as opposed to a plastic one.
And finally, cloth drip is pretty straightforward. I happened to nail my first brew, thanks to Barismo's education guide, which is the best one around. Check it out if you're interested in enjoying clean and deliciously syrupy coffee.