For pills as well, if you're the kind of person who has a cocktail of prescription drugs wherever they go... I had an old, hard-shell AF one in that role for years.

Generally, I fold clothes (using the fold-back-in-two-halves-then-sleeves-into-the-middle method for shirts and t-shirts) and put them in poly bags by category - as well as carrying a couple of laundry bags. That way, if I'm moving around, I never really have to unpack - I know I can easily pick out what I want from each bag without disturbing the rest, and then just lob the bags back in the suitcase when I move on, and easily sort out the laundry if I need some done en route.