When Swiss designer Till Könneker moved into his new apartment, he loved the clean, minimalist design...but not the fact that it had zero built-in storage place. So, he came up with this clever storage cube to house his bed, book and record collection, and shoes and clothing. Oh, and this is the best part:
Boom! Hidden storage for all that stuff nobody has any business looking at. Till drew up his design and shares the plans at Behance. Though the plans are sparse, they definitely give insight into the process. Of course, to create a unit that you can walk into, you'd have to have pretty tall ceilings, but those tend to be the norm in places like this. (These look to be around 10') You could pull off a similar idea in a standard 8' space, turning the hidden storage into more of a crawl space.
See more at Till's Behance page: The Living Cube