The “Eco Shoes Dryer” from Life in Detail are plastic shoe trees filled with silica gel which absorbs the moisture from your shoes after they’ve been worn. When full of your foot juice, the Dryer can then be plugged into the wall to accelerate the evaporative process, presumably with a small fan. (Sci-fi tech says they use a battery inside to power themselves during the drying phase, but that doesn’t make sense to me. Silica absorbs moisture just fine without any electrical assistance.)
Getting moisture out of shoes helps prevent bacteria growth and subsequent bad smells, but is also good for keeping leather from cracking.
Product Page (Japanese) [BE-S.co.jp via Sci-Fi Tech]
