At 2:08:34, The character of Dileep,(Played by Raj Singh Chaudhary)from another of Anurag Kashyap's Movie called Gulaal(2009), can be seen doing a cameo, in a blink and miss scene. Also you can see the same set up and Dev(Played by Abhay Deol) in Gulaal.
In Gulaal, in the scene where Dileep Kumar Singh is being ragged for the first time in the hostel room, one of the persons in the room is dressed (with the eye lashes & similar makeup) as the droogs from A Clockwork Orange
In Gulaal there are several homages to the Tarantino movie e.g. a kidnapped person being shot suddenly by someone not in the frame, the fictional brands of beers (Democratic & Republic), then someone getting shot in abdomen and surviving for quite a long time, etc.