My dad's favorite car was his 1952 Willy Aero. It remaind his joy for over 13 years. My latest small coffee brewer is an Aerobie Aeropress. It oughta last as long as the 50's Aero. It has become my favorite.
The Aeropress is a small piston and cylinder about eight inches long and two inches in diameter made from translucent, thick plastic. The cylinder has a screw-on bottom which holds a paper filter disc. The piston has a rubber bottom part/plug that fits tightly into the cylinder.
To use, place the cylinder with filter+holder on top of your cup, a sturdy one -- you will press down hard. Pour in some grounds, moisten them with a bit of hot water, put in some more hot water, and stir the slurry for a few seconds with the provided paddle. Insert the piston into the cylinder, and press down to force the liquid through the paper filter into your cup. The grounds are trapped between filter and piston. Remove the assembly from your cup, unscrew the filter holder from the cylinder, and press the piston in all the way to expel the puck of grounds. Rinse off the rubber bottom of the piston and the screw-on filter holder in a smidgen of water. The whole process from charging with grounds + water to coffee + ready/for/next/cup takes a minute.
The resulting brew can be quite strong when using a lot of finely ground coffee per amount of water, as the manual recommends. Dilute the brew with hot water to make something Americano-like, or with steamed or foamed milk to make latte-like or cappuccino-like drinks. (The "-like" is in deference to those who consider "espresso" to only apply to drinks made according to certain European standards of preparation. See below.)
I use it a couple of times per day, at home and on the road. I feed it 1.5-2.0 grams of finely ground beans roasted at home a day or three before, per ounce of 180-190F water. I press half of the water through the Aeropress and put the rest of the water directly into the cup, before or after pressing, for dilution.
I've played around with water temperature, stirring time, fineness of grind, ratio of coffee to water, darkness of roast, and pressing force. There are so many variables that you can tune this infinitesimally to your style. After around a month, I stopped fiddling and measuring, leaving more time to enjoy the results.
The results are just great with me. I almost never use my Gaggia true-espresso machine any more, and my small-quantity drip coffemakers have mostly been retired. As a particular comparison, the sediment in brew from a french press never excited me. This device lets absolutely no sediment through its paper filter.
Some engineers would call the Aeropress'es design elegant. It is as simple as can be but it does exactly what it's supposed to, i.e. extracting great flavor from great coffee efficiently. It is especially time efficient with its rapid brew time and minimal cleanup effort; of course if you need to make eight cups this tiny device has to be used several times sequentially. The rubber part of the piston scrapes clean the sides of the cylinder so there is literally no routine cleanup needed inside the cylinder. It is minimalist - only four parts and it comes completely apart without tools. It is thoughtful - the stirring paddle is long enough to do a thorough stir and shaped so it can't scrape the bottom where it would tear the paper filter. It can reuse paper filters if they are rinsed when rinsing the filter holder - lots of them are provided, enough to make several hundred cups if one reuses each several times. Except for the rubber part of the piston which might erode after a long time, there is nothing to wear out and nothing to break. It should survive for a decade or more. It is environmentally efficient with its small amount of cleaning water and minimal waste; the grounds without filter paper will compost nicely.
This is the most useful $30 I've spent out of about $600 on coffee apparatus in the last couple of years. I especially like using it on the first roast batch of a new bean variety, right out of the roaster.
Are there any downsides? Yes; they're far outweighed by the upsides. For $30 what do we really want?
I'm using up too much coffee, due to drinking more of the tasty results and making a stronger brew than before. It is possible that my very short extraction/stirring time and lower temperature than the >200F usually recommended for "drip" are not resulting in optimal extraction. Of course one can go longer and/or hotter. The downside here is really that there are too wide ranges of too many brewing variables to find one's own best parameters quickly -- Aeropress is a fiddlers delight but it is not for the impatient. The recommendations provided in the manual led to far too much coffee use (about 2.5g/ounce water, over double what I use in other brewers) and too-cold a result (starting brewing at only 175F) for my tastes.
The specs claim one can make on the order of 24 oz per brew, for 4 cups, after dilution of a concentrated extract. To prevent over-bloom of freshly roasted beans, I restrict my volume to "2" on the cylinder's graduations, about 12 ounces of final liquid after 50% dilution, and no more than 25g of coffee. This is adequate for one person but small for two unless one is making small cups. (So run it twice ... Yet another variable.)
The box is best ignored. I bought the device without seeing the box. Had I seen it first in a store and not visited CoffeeGeek I would have dismissed the product as being overhyped. No, you can't make standard "espresso" with this little pressure. And regardless of terminology, the best out of my Carezza or routine products from a nearby Gimme Coffee! can bring tears to eyes; my average Aeropress brew merely produces wide grins.