Uwe Schüler from the Kulturgüterschuppen in Dusslingen has designed an easy-to-solder Thermin for small budgets. It is based on the CMOS 555 chip and sounds very good for components around 15.-€. I will make a video soon, when I have practiced enough with it.
drkmbnt "Jammin' with the CMOS-555 Theremin" from Wolfgang Dorninger on Vimeo.