Ever since Big Brew day I have been meaning to send this note. A few people seemed surprised to learn you could buy a cheap but good refractometer for ~$25 including shipping. I have one of these and it is the same thing as the one we were using that day which someone had paid more like $50 for. These are metal, have ATC auto temperature correction (I think because of the metal body?), a hard case, many pipettes, and all you need.
You can see an example here:
Or search for the text: Brix Refractometer ATC Sugar Wine beer
It will come to about $23 including shipping, so that's not a bad price for a cool tool.
cheers,
don