I posted this to a lever thread, but thought I should give a heads up here.
Dwyer Instruments (Love division) is manufacturing and selling a thermocouple temperature switch (similar to the Brewtus stock controller) for $50. This is a simple on/off control with programmable hysteresis (e.g. turn boiler on at 122C, off at 124C). The really nice feature is that it includes a 16 amp rated contact, enough to drive most home espresso machine heaters comfortably, therefore does not require a separate SSR.
To buy: http://www.dwyer-inst.com/htdocs/temperature/SeriesTCSPrice.cfm
For many applications, one wants easily settable reasonably tight temperature control, but the final shot temperature has so many other factors that PID is overkill. Steam boilers on dual boiler, lever or HX machines, as well as the boilers on smaller machines like the Silvia, come to mind. This unit could cut the cost to 1/4 of a PID, and simplify installation.
I've bought one to use with my Peppina. I will also assess whether it's useful for the Tea's steam boiler and for an ultra secret temperature control scheme I'm contemplating.
OK, you've twisted my arm. See my post