One more incredibly cool tool that I would love to have, but do not have is a scace portafilter. For measuring the temperature of espresso extraction. It was invented by Greg Scace and is used for setting up espresso machines. You can find it at a few places including Espresso Parts North Westhttp://www.espressoparts.com/EP_THERMOFILTER2
This is a clever invention that can be inserted in the grouphead of some espresso machines (if the portafilter matches). It is available in particular for La Marzocco machines and many 58 mm grouphead machines such as the Rancillio machines. ON the other hand it does cost almost as much as the Rancilio Sylvia alone.
Another catch with it is it does not work all by itself. You need to hook it up to some form of data logger. Many people use the Fluke 54 II model to monitor it, but that is not too cheap, either. Here is a typical price form amazon.http://www.amazon.com/Fluke-FLUKE-54-2-60HZ/dp/B000L9TTNO
Combined the products run you $545 + $369 = $914, in other words as much as a nice espresso machine.
This is why I have always lusted after one and never had one. It would be great fun to have one and figure out exactly what temperatures various cooling flushes led to in the portafilter, but I will never have one of my own.
On the other hand there is a guy who rents (or at least used to rent) one for $61 a week that makes it a little more reasonable.http://www.home-barista.com/marketplace/for-rent-scace-thermofilter-and-fluke-54-ii-thermometer-t11479.html
It still is probably more than I will ever spend since I know how to repeat temperatures and I know how to raise them and lower them relative to previous shots and in some sense it does not matter exactly what number is associated with the temperature at which I want to pull a given espresso as long as I can repeat it.
It still does not kill my wish for one though!
By the way, I have invented poor man’s Scace devices of my own where I drilled a hole in an old basket and put a temperature probe in it, but that is not nearly as good at imitating what is going on in the coffee puck.
Now before one jumps to the conclusion that this is a device with no real market except the extreme fringe we should realize that it is really developed for people who maintain many, many machines, perhaps servicing them, for example, for hundreds of coffee shops. For them this device is a no brainer.
For me alas it remains just a wish.