or how about the Kithaus K3?

The Kithaus K3 is easily put together, and the components are ecofriendly. Designed by Tom Sandonato and Martin Wehmann. buy it at DWR.

atelierworkshop

Katharina, this is what your guesthouse/atelier should look like. I would come visit every day! These are portable holiday-homes made by atelierworkshop. you dig, sis?

LTL architects

I first stumbled over LTL architects a few years back, 'cause I had fallen in love with the interiordesign of the now closed Ini ani coffeeshop in New York.
LTL architects do amazing work. The pictures above is from Fluff bakery and Tides restaurant, both in NYC. How about those waves in the ceiling of Tides. Wow! pictures borrowed from the LTL architects-website

4-pli

4-pli is a young architectural firm based in williamsburg. I love their Puzzle Conference Table, it's made of seven individual desks that puzzle together to make a large conference table. I can't imagine any shady deals happening around this baby- it's too nice for that. 4-pli makes an effort to participate in the whole process from the paper to the finished product- which must be satisfying, when the products come out this nice.