The Calypso by designer Brandon Allen takes the concept of the futon, updates it to the year 2009, tweaks it a little bit, and then kicks it square in the nuts. The super-jointed loveseat concept quickly converts between workstation, regular sofa, coffee table, and weird waiting-room-type seating area.
Something like this looks as though it’d fit in really nicely in a small space. You could probably even get away with throwing one of those rollable mattresses on top of the coffee table configuration for the overnight houseguests that barely fit in your apartment.
It appears to be just a concept at the moment, but A) do you like it and B) how much would you pay for it?