Shell
#!/usr/bin/env sh
Python
#!/usr/bin/env python
Ruby
#!/usr/bin/env ruby
Perl
#!/usr/bin/env perl
JavaScript
#!/usr/bin/env jsc
Need link to jsc (JavaScript interpreter).
$ ln -s /System/Library/Frameworks/JavaScriptCore.framework/Versions/Current/Resources/jsc /usr/local/bin/jsc