While drinking my tea, I found myself staring at this strange sill standing up behind the bar. At first I thought it was brewing moonshine or something, until I realized that the output liquid was black. Basically, a pot of water sits above a bin of coffee grounds and filter, slowly dripping water through at the rate of about two drips a second. This seeps through the coffee and filter, eventually spinning down the condensation tubes and into a waiting beaker. I'd never seen anything like it.
I asked one of the waiters to explain this strange contraption, and he informed me that it's a Dutch-style cold water drip filter: each drop that falls into the final beaker takes many hours, or even a day, to make it from top to bottom. This slow-brewing method, using completely cold water, apparently reduces the acidity of the final drink, and even (he claims) makes it naturally decaffinated.
I should have asked for a cup, but I was on my way out.