I PERSONALLY have 2 windows PC's a mac and a linux. =) I also own a Acer Laptop for school (college courses).
WE have a computer in the family room and my brother and dad EACH have a laptop.
I prefer my laptop and the linux just cause I grew up with linux and it's easy to learn the INS and OUTS of linux. WIndows has too much hidden stuff that you actually have to look for to make your system go faster. Mac is alright but not enough programs to run on it. =(
Laptop - School Work and has an external full of movies and games
Mac - Just to explorer the intracies of other computers
Linux - Just to explorer the intracies of computers
PC's - INternet and Graphic Design
Just one computer in my house. I'll eventually aim for getting two desktops and a laptop since my spouse and I always fight for computer time. I like being the first one up in the mornings. *evil grin*