The B double vertical strokes is a Unicode symbol? What is its code? I can't find it on any list of Unicode symbols (maybe I'm not looking in the right place?).
Yep. Unicode defines symbols like this using "combining" characters
(the "already combined" characters exist only for compatibility with legacy encodings such as Latin-1), so for B⃦ you do:
This works to some extent for all possible combinations (apparently some people are getting blocks, though?).
From there, fonts can specialize with "ligatures" (renderings that represent a sequence of characters) - which is where things can definitely use improvement.
Ok, so now I know why it looks shitty on my and many other systems. The vertical strokes are in different places depending on the program I use. In my chromium browser they are too far right and in gedit they are in addition to far right too short.
Knowing it is actually a double-symbol makes me all the more favor any of the single-symbols that at least should look consistent on all systems that manage to display something:
฿ or Ƀ.
The $ symbol being used for many many currencies should be reason enough to not have a problem recycling the Baht symbol for Bitcoin. Here in Chile they also use $ for Chilean Pesos.