I saw this on a camping blog and thought it was a very good idea. We just went on a road trip and I tried it out - much more compact and easier to use than other ways I've tried to organize meds in the past (especially when I would just put them all randomly together in a small baggie haha!). Each day of the week is holding a different pill (aspirin, tylenol, benedryl, etc.) or vitamin, to remember what's what I put a piece of paper in the bottom of each compartment and wrote the name of the med on the underside. When packing for a short trip I don't need the whole bottle, this way I just have a few in case I need them and they are all organized together in one place. A little mini medicine chest!
2021 update - just fyi I still use this exact pill organizer, I take it everywhere in my backpack - it's so handy!