the nuvola rossa, designed by vico magistretti in 1977, has the look (but not the functionality) of classic collapsible furniture. it's a beautiful object, but it doesn't actually collapse, and seems to hide nearly as many books as it displays. (correction: it does collapse. i can't remember where i got the notion that it didn't. sorry)
parallel shelving (below) by stephen burks is a true collapsible that retains a light, open look.