The title basically says it all. I'm looking for suggestions for fun, stimulating dog toys that my dog can play with alone (i.e. without me having to do anything to get the toy to work, not when she's alone without supervision). Would prefer them to be small-ish and easy to put away in a cabinet or closet when not in use. We live in Manhattan, in a 1 bedroom apartment without a backyard, so stuff like automatic ball throwers aren't going to work. My apartment isn't small by NYC standards but I certainly don't have space to install anything sizable from a wall/ceiling/etc.
Backstory: I have a 10 month old Keeshond who doesn't love to play with toys by herself. She will happily play tug (and similar games) with me, loves to run around with other dogs at the park, and enjoys training (we do obedience and agility). She also likes to chew, and has several Benebones, as well as a steady supply of Himalayan Dog Chews. We have a few toys that, in theory, she could play with alone (Kong Cozie, Hide-A-Squirrel, and such) as well as basically every type of Kong which I use for all her meals. She likes toys filled with food, and I try lots of different recipes in the Kongs, but I reserve the Kongs for when she's alone (i.e. when I go to work).
Any suggestions are appreciated.