Great work do far, really liking the design and the hope to get it down to 0.99L for the record. But you mentioned making a higher case for those wanting to use a 1080 with a better cooler. Would you also consider increasing the width of the case by around 20mm so you could add some 40mm fans to the left of the GPU pushing air down the case. Noctua make some quiet 40mm fans that can be PWM controlled: http://noctua.at/en/products/fan/nf-a4x20-pwm
The base is flat.
Yes, nano case is already available in 1.6L (quiet, cold, GTX 1080) and 1.0L (world record edition, GTX 1060).Will you ever make the case a bit bigger? I'd love to get a STX case that's quiet and has viable temps, all while being smaller than a ITX case such as the S4 Mini. I know the version you are making is for the world record, but i am very interested in a PC this small and i would definitely buy the case if what i am suggesting was met. Great job overall guys!