A global chain of fashionable stores which began as a budget retailer, Muji can be translated as 'No Logo', and in fact is one of the examples given by Naomi Klein in her book No Logo to illustrate the complexity and paradoxical nature of corporate 'branding' and the means that exist to attack it.
Muji items have no labels, logos or designs, and hang in the brightly-lit windows on headless mannequins. For clothing, they focus on 'natural' fabric colours such as brown, grey, white; silver is the most common theme for man-made objects, of which they sell a seemingly random array including toasters, bicycles, business card holders, pens and curtain rails.
Muji stores became fashionable (and therefore expensive) in Europe precisely due to the lack of marketing and logo, which in a well-documented stroke of irony became an excellent marketing tool for attracting the hard-earned and easily-spent cash of young, trendy, fashionably anti-corporate consumers. If Muji ever decided to run a visual advertising campaign based around a single image or concept, it should be Rene Magritte's Ceci n'est pas une pipe.
Update: gn0sis informs me that Muji is short for "mujirushi ryouhin", which literally means 'unmarked good products'. He says: "The original idea was to strike a middle ground between 100-yen pastel crap and overpriced designer crap -- a small-scale Japanese IKEA, if you will."