Movie developing & processing tanks for super-8, 8mm. and 16mm.: I always use the Lomo processing tanks, suitable for super-8, regular-8 and 16mm. They come in different sizes. With the 100ft. version you can develop 2 super-8 cartridges at once. Sometimes difficult to find.
What's it worth? Take a look at this list of: sold Movie Tank for a value indication.