It's a small thing, but I think supporting the "-V" and "--version" flags from prove would be nice. The patch is essentially a small addition to GetOpts:

    'V|version'     => sub { print_version(); exit; },
[download]

And then:

sub print_version {
    printf( "prove v%s, using Test::Harness v%s and Perl v%vd\n",
        $VERSION, $Test::Harness::VERSION, $^V );
}
[download]