Obscure dpaste.com fact of the day: item IDs are base 32, with the digits chosen to minimize ambiguity. No zero or one or the capital letters that look like them. In case you need to read one to somebody or transcribe it without copy/paste. (They're also case-insensitive, though uppercase is canonical.)
@Dpaste Tor's Onion addresses use a similar unambiguous alphabet. I believe many things also use such a set (unless they are expressed in a higher base).
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