I know RFC2324 was an April Fools joke. However, it seems pretty well thought out, and after reading it I figured it wouldn't be out of the question to design an automated coffee machine that used this extension to HTTP.

We programmers love to reference this RFC when arguing web standards ("418 I'm a Teapot lolz!") but the joke's kind of on us. Ubiquitous computing research assumes that network-connected coffee machines are probably going to be quite common in the future, along with Internet-connected fruit and just about everything else.

Has anyone actually implemented a coffee machine that is controlled via HTCPCP? Not necessarily commercial, but hacked together in a garage, maybe?

I'm not talking about just a web server that responds to HTCPCP requests; I mean a real coffee machine that actually makes coffee. I haven't seen an example of that.