Kildwick EasyLoo Camping Toilet / Compost Toilet with Fan 5 V Black : Amazon.de: Sports & Outdoors
The Angel 'Floozy' Compost Composting Toilet for Boats and off-grid living | eBay
Check out KILDWICK.com for some awesome d.i.y. kit's or already assembled composting toilets. They come with everything you need for less than half the cost of the leading Natures Head toilet :