Core77 is running a great 4-post series about the design and engineering of stairs, including innovations in transporting heavy objects upwards, simple strategies for fold-out flights, and (my favorite) smart ways to get stairs doing double duty as storage space. In yesterday's stair storage post, the author describes researching DIY approaches to building sturdy treads that can contain hundreds of books.
The most dazzling example of success in this arena is a staircase at an apartment in London (featured at Apartment Therapy), where the design is really more bookshelf than staircase, but the shelves extend in tiered layers, with each protrusion adding up to a walkway to the second floor. I can only imagine the joy of being the renter who lucks into this place. The fourth in the series features a bunch of videos in which engineers test stair designs using robots. This post veers into serious geek territory but it's fun to watch the stair-climbing robots take on the steps, and interesting to see how designs are developed based on this research.
If you love to stare at stair porn, you'll probably enjoy this many-angled examination, and maybe get inspired to design your own high-performance staircase.