I'll just butt in here and say that while the URI format is nice for alternate schemes, it is not nice for accessing files.
The general case in most programming languages is to assume that a non-URI "file" name is local, specifying file://wherever/whatever/filename is unnecessary additional syntax. Also, perhaps only URLs should be permitted; they do after all specify a location. I'm unsure whether this should be part of a central specification to Perl 6 or part of a module. I think I like Hinrik's original proposal. Oh, and regarding file names in Windows, this document should be a pretty definitive guide: http://msdn.microsoft.com/en-us/library/aa365247(VS.85).aspx -- Jan