I've bought an A4 wipe-clean whiteboard (cheap from stationers) which is brilliant for reminding Mother what day it is and what's happening.
We've tried two different clocks-with-date, and there's still a need: ideally an analogue clock with day, date, month? As we're living with Mother we cope with one which needs to be manually tweaked at the end of 30/28-day months, though I can see that would be a problem for people without a resident carer.
I'd like to find (perhaps could if I looked harder) some sort of a locating device to tag Mother's diary (small pocket size): I've spent hours of my life looking for it (in drawers, under pillow, in pockets, down side of armchair, under anything and everything, up sleeve of jumper...) as she's obsessed with it and gets terribly upset if she can't lay her hand on it. (Tying the pencil to the diary with a string was one inspiration - only one item to lose now, not two!) I think the sort of thing designed for key rings might work, but ideally something just the size of a sticker, with a non-losable gadget to locate it.
Hope this helps. Pam