Wincest is when you screw around with your PC.
Combination of Windows, the OS, and incest, since with the amount of time you spend on your computer it's like a
family member. You usually get some sort of STD from it, since the virus disabled the firewall.
It includes but is not limited to: adding RAM, updating drivers, installing new software/hardware, and actually humping
the damn thing because you're so lonely.
It is also used to describe awesome incest, but that's a swiftly aging meme.