Here's a list of characters (probably not the best resource) http://www.theworldo...tuff.com/characters/
The problem seems to be the convenience of being able to use alternate characters; it's not too practical to start using a system that you can't type with standard keyboard shortcuts. With my UK keyboard, these are legal characters readily available to use:
¦ (this is the one I mentioned above, named "Broken vertical bar", this isn't the "pipe" character.)
I've seen ~ used instead of \ to indicate directory structures (maybe that's common?).
I guess you could use:
¦ for |
¬ for \
~ for /
~ for \
Or double up common elements (just using similar "slants" within the characters) like:
%% or ,, or ## for /
`` or && for \
It would be nice if there is a standard that people have already embraced, I agree.
I've just realised it would be quite difficult coming up with similar looking characters for things like * and ? (well, all of them really). The large problem is not being able to use characters that are going to cause confusion because they are used reguarly, e.g. would it be bad to use ; in place of : etc., etc.