I dunno what weird character encoding buffo uses, but curly brackets are in the 7-bit ASCII set, and any sane 8-bit ASCII extension (including the widely-used ISO 8859 standard) won't touch them.

Still, HTML entities are a good way to display non-english characters without worrying about how to tell the browser which encoding to use, and they're the best way to use characters from totally unrelated languages in the same document (like using some kanji in a German website about the Japanese language).

The full Unicode character set can be accessed as HTML entities through the pattern �, substituting the unicode number in hexadecimal for the zeroes.

However, there are some negative points, too. Editing the source code is incredibly painful if there are a lot of HTML entities in them and your editor doesn't automatically translate them both ways (which I don't think is possible while retaining full flexibility). And the entities won't show up in a string search for the "normally" encoded characters - your website on "Österreich" won't be found by someone looking for information about "Österreich" in a search engine. The same is true for Everything 2 node titles.