Area Rugs: The above picture is some of the selections of area rugs from Natural Carpet Co. (http://www.naturalcarpetcompany.com/). They are hand knotted Tibetian wool and silk. Natural Carpet Co. has a new line out with Roger Thomas consisting of the wool and silk area rugs, abaca area rugs, and abaca carpet. Personally abaca seems more like an outdoor surface or something to give a wall an interesting texture. I like area rugs, in general, for the versitility they offer. Hard wood floors are nice and easier to clean, but the softness and sound absorbion that carpet offers is nice too. The compromise is area rugs!
Carpet: Granted, I don't care for the color scheme in this picture it does show you the carpet. I tried to copy a picture of the swatch from Karastan (http://www.karastan.com/), but it wouldn't let me. So I settled for this instead. Carpet comes in many colors and patterns. It also comes in various textures including: berber, loop pile, cut pile, and shag. Carpet gives a space a soft, cozy feel. The downside is that it is costly to install and care for.
Vinyl: Pictured is plank vinyl from Armstrong (www.armstrong.com/flooring) in bamboo. Plank vinyl has the look of natural hard wood floors, but is easier to install and care for. It also won't dent or scratch as easy. Vinyl also comes in tiles made to look like stone, or sheets that have a pattern already. It's great in kitchens and bathrooms since it's more water resistant that real wood or carpet.
Marmoleum: This newer product is the "green" replacement of linoleum. It is made from natural linoleum, linseed oil, wood flour, pine rosin, natural pigments, and a jute or cork backing. It is natural anti-static so it repels dust, dander, and other allergens; which is why it is certified to be allergy and asthma safe, and is ideal for use in schools, hospitals, and homes. Since it's made from natural products it won't off-gas. Also, when the linseed oil oxydizes with the air over time it cures and hardens even more making the product last longer. Forbo Flooring Systems is a main supplier (http://www.forboflooringna.com/Residential/Products/Marmoleum-Click/). EcoHaus (http://ecohaus.com/C-696/marmoleum+click) in Seattle sells it as one of their products, and that's where I found more information about it.