One thing you have to keep in mind, though, is that shift and push are expensive. It's a lot cheaper to index++ % @spin.

It doesn't matter for this code, since you're only going to shift/push once per second, but you might want to keep it in mind if you ever need to do this kind of array looping in a tighter loop.

ObBenchmark:

#!/usr/bin/perl -w

use strict;
use Benchmark qw(cmpthese);

my $i=0;

my @spin=qw(- \\ | /);

sub spinShift {
    my $spin=shift @spin;
    push @spin,$spin;
    return $spin;
}

my $ndx=0;
sub spinNdx {
    return $spin[$ndx++ % @spin];
}


cmpthese(-2,
        {
            spinShift => \&spinShift,
            spinNdx   => \&spinNdx,
        }
     );
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On a perl 5.8 Linux system, using an index clocks in 133% faster than using shift/push.