I like weird characters in mp3 file names, because I want the file names to contain the exact titles.

Often it's not difficult to use the command line in a way that there's no problem with special characters. For instance, rather than writing Perl code like

`mv "$url" "$title"`
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you can use

system('mv', $url, $title)
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or on GNU:

system('mv', '--', $url, $title)
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or even

rename($url, $title)
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This will work perfectly with all kinds of strange characters in file names. Plus, it's more secure.

Another problem some people face is shell stuff like this:

for i in `ls`; do
    some_command $i
done
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Of course, this will not work if there are file names with spaces (or globs).

However, this will work fine:

for i in *; do
    some_command "$i"
done
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