So, as far as obscure questions go this one takes the cake. But it’s fairly workoutable and fair-fodder for Boiledbeans, so here goes.

What’s so special about the circle?

Cracked by: jayanth, Rogi, Shrey Goyal, finkle, Manish Achuth, Anonymous, Sumanth Patlolla, rickde, Bharath, Ananth, badideabear, Bipin Banavalikar, Mayukh Bose, KK, raklodramA, Amarendra Kumar, Raghuvansh and piezocake