Behringer 150 Ring Mod is good stuff.

[mimidancer]

Over the weekend I revived the Behringer 150 module from the System 100 series. I paid $49 U.S. Great deal for the module with pink and white noise, an LFO, a sample and hold circuit, and a ring mod. The face is metal and the build quality in the System 100 series is awesome. In eurorack modules, one could pay a lot more for less. I have most of the system 100 modules from them now and can't say enough good things about how pleased I am with them. If you do not have a rack but want to start, Behringer makes getting started easy on the wallet.

[mimidancer]

I guess they are not into inexpensive ring mods. GTK