This 21st century trend started with Sweden's 2005 Turning Torso building, then quickly was adapted and modified by Frank Gehry for what became 2011's 8 Spruce Street in Manhattan. Now the twisted apartment building seems to have become its own typology, to judge by recent proposed works by both Urban Agency and Sou Fujimoto:

↑ Urban Agency's code-savvy twisting apartment building.

↑ Sou Fujimoto's Abre Blanc apartment building.

Urban Agency's apartment building twists not just for an aesthetic thrill, but as a way to legally increase the total floor space by 40 percent by artfully shimmying through France's planning laws. Sou Fujimoto's unfurling, frond-like patios on Abre Blanc are thoughtfully designed purposefully to suit the structure's surrounding Mediterranean climate by embracing an outdoor lifestyle. MAD's "Marilyn Monroe" 2010-2012 Absolute World towers in Mississauga, ON took a more curvaceous and populist approach, as the final design was voted on by the Canadian public after the six architectural firm finalists had been jury-selected.

↑ MAD's Absolute World Towers in Toronto

Santiago Calatrava's Turning Torso tower in Sweden is not only the tallest building in Scandinavia, but takes its inspiration from the marble sculpture "Twisting Torso" by Calatrava, which was meant to simulate the complexity and fine-tuned turning power of the human spine. The top floor is turned a full 90 degrees away from the ground floor.

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↑ Santiago Calatrava's Turning Torso

Meanwhile, Frank Gehry's twisted, veiny 8 Spruce Street is inspired by...well, on opening day, Gehry turned toward the tower and remarked: "No Viagra."

↑ Frank Gehry's 8 Spruce St.