We technically have 5.
One for each of us: DH in his closet, me in my closet, DDs in each of their rooms. Everything goes down the laundry chute (LOVE it!!) then gets sorted into a three-section hamper: white/hot, medium and dark. Plus a separate pile for any delicate stuff.
Works so far. I am going to have to revisit the laundry set up when we move, laundry is on the 2nd floor and our current laundry is on the 1st (and DH and I are going to be sharing a closet again). I am used to just wandering in and throwing in a load whenever. I think I am going to have to be more purposeful b/c once I am downstairs I will certainly forget about any laundry going upstairs.
"Every mother needs a wife." - Amy Poehler, Yes Please