RepRap

From Opendildonics.org

RepRap is an open source style rapid prototyping project with the end goal of being able to make a machine that can make a copy of itself.

In its current state it can recreate all its plastic parts. In the future it should be able to print its own circuit boards and cut its own metal parts. Assembly seems to be beyond the scope of the current roadmap.

RepRap version 1.0 (Darwin) costs about $400 to build and can extrude parts in CAPA, HDPE and ABS. Or you can build a RepStrap Seedling like the McWire version 1.2 for around $250. Many of the parts needed to build your first RepRap (like the electronic components) can be purchased at the RepRap Research Foundation.

While they do not have parts files online for printing dildos, it's only a matter of time before someone designs one in Blender and starts a whole new trend.