Things I've learned about my Aeropress
http://aerobie.com/products/aeropress.htm

Ignore all the obsessing about using it upside down, pre-watering the filter and so on. Only 3 things matter, the quality of the coffee, the temperature of the water and emptying it as soon after use as possible so the rubber bung doesn't harden and lose it's seal.

Coffee.
I like a good strong Italian style taste without it being too aggressive.

- Mainstream. Tescos Italian Blend, Lavazza Black, Carte Noire. These are all perfectly serviceable, easily available, every day, fine filter or expresso grinds that just work and are predictable.

- Algerian Coffee Shop, Soho, London at http://www.algcoffee.co.uk/

"Formula Rossa" their main blend that they use for the take away coffee they serve in the shop. Straight forwards and recommended. Ideal for an Americano 
"Cafe Torino" For a stronger Expresso/Ristretto cup, try this one. It's a bit more aggressive than the Formula Rossa.
"Velluto Nero" After Dinner Expresso. Gorgeous but too much for every day drinking.

A note about grinds. I find a straight expresso grind works best. In the Algerian Coffee shop that's a "4" on their machine. Finer than filter or french press, but not so fine that you get finings and dust in the bottom of the cup.

Water Temperature.
After the choice of coffee this is the single biggest factor in the quality of the end product. You need to aim for 80-85C. This is tricky without spending huge amounts on clever kettles or messing around with thermometers. Any higher than that and you'll "burn" the grounds and make the coffee more bitter. The simple trick is to boil about 750ml of water (1/2 a kettle?) and then wait 30-60 seconds after the kettle turns itself off. So don't start assembling the Aeropress, coffee, filter, mug and so on until the kettle has boiled and by the time you're ready to pour in the water, 60 secs will have gone by and you'll be about right. 

Spares.
http://www.hasbean.co.uk
http://ablebrewing.com
Rubber bungs, filter caps, filters, stainless filter disks, tote bags, etc, etc. The stainless filters didn't really work for me. The paper filters are cheap and easier and just work. There's a rubber travel cap but it's a bit inconvenient and only really works for storing a few days supplies of filters in the plunger. 

Cleaning.
Just empty the Aeropress immediately in the bin and wipe the base of the rubber bung under the tap. Then store it either in two pieces or with the piston all the way through so the bung isn't under pressure. Otherwise the bung will eventually take a set and won't seal any more. It's pretty much self cleaning so just a quick rinse is all that's needed.

Recipes.
Don't bother with all the complication. Don't worry about pressing air though the grounds. Don't bother with the upside down method. If your cup is too small to fit the aeropress in the top, use the hexagonal funnel.

White Americano or filter coffee.
This is the typical every day mug of coffee.  Put on your 750ml (ish) of water in the kettle. When it boils get the mug, aeropress and stuff out of the cupboard. Assemble the paper filter and cap and set it on the mug. Add a 15ml scoop of grounds. Fill slowly with hot water to the 3 mark. Give it a quick swirl with a spoon to settle the grounds. Wait till it drips so the surface is down to the 2 mark, say 20 seconds. Insert the plunger and press gently down till the grounds are squashed. Add a splash of milk. Empty the aeropress and wipe. Done! Enjoy! 

Double expresso.
As above but 30ml of coffee grounds which is the scoop that comes with the Aeropress. Fill with water to the 2 mark. Let it drop to the 1 mark and press.

Thermos.
I have a stubby 15fl oz, 400ml thermos which holds about 2 mugs worth. 30ml or 45ml of grounds, fill to the 4 mark. Press when it drops to 3. Add milk till it's the right colour. Top up with boiling water.

Improvements.
I struggle to think of any! I think there's potentially a redesign that makes it easier to travel with the kit and a week's supply of filters and coffee. Perhaps the cap could screw onto the other end of the plunger.

Just occasionally the seal doesn't quite work between the main cylinder and the cap. I'm not quite sure where it leaks from but it can lead to dribbles down the side of the mug.

Anyway. If you haven't tried one and you like coffee then get an Aeropress. for making one or two cups of coffee it's way better than Cafetieres, Mocha stove machines, drip filters and so on. And it's considerably cheaper and easier than expresso machines. And even if the pod machines are convenient, they're just WRONG. The old school filter coffee machines still work best for 4 mugs and upwards.

So I really don't think there's anything better for small quantities.