I like to think I have only some customization, and it certainly looks that way in this thread. But I guess compared to 'normal' people (i.e. the type that doesn't parttake in threads like this one) it's still a lot.
It's basically some configuration scripts, several dozen default softwares, 100-200 aliasses, a few browser extensions (some self-made) and a whole bunch of custom hotkeys.
It doesn't seem like much to me, but it's apparently enough to make my computers nearly unusable to colleagues or family people.