When 3D printing a particularly complex object, you often need to incorporate additional support structures into its design, given how the layer by layer additive process works. And with 3D systems new water soluble filament, those unwanted support structures can easily be dissolved away with a little H2O.
Removing support structures usually involves some very careful work with a hobby knife to ensure that the plastic parts you want to remain don't break off too. The more intricate an object you're 3D printing, the more nightmarish that process can be. There are already special support filaments that can be dissolved away using a chemical bath, but 3D Systems new Infinity filament dissolves away using regular old tap water.
Once dissolved the non-toxic filament is apparently safe to just flush down the drain, but larger pieces can be manually removed and discarded in the trash once slightly softened. Because it's designed to be non-permanent, the material doesn't have any colouring which could make it difficult to ensure it's completely removed if the rest of your 3D-printed object is the same shade. But a long soak should ensure every last bit disappears.
Designed for use with 3D Systems' Cube 3D printers, the new filament is available in $US49 or $US99 cartridges depending on the size of the machine you're using it with. And it's got a shelf-life of about a year, but we all know even 3D printer cartridges need replacing far more frequently than that.