I dont know if it's efficient, but it works =)

# indexed array
@array = sort { (-1,1)[int rand 2] } @array;

# or trinary alternative
@array = sort { int rand 2 ? 1 : -1 } @array;

[download]

Hope this helps

Update

In fact, it's really a bad idea to use this for randomize an array...

See the result of this script : 
#!/usr/bin/perl -w

use strict;

my @array = qw( peach banana mango orange apple cherry );
my %result;

$, = "\t\t";
$\ = "\n";

for(1..10000) {
    
    @_ = sort { (-1,1)[int rand 2] } @array;

    for(0..$#array) { $result{ $_[$_] , $_ }++ }
    
}

print '' , (0..$#array);

for my $fruit ( @array ) {
    
    print $fruit , map { $result{ $fruit , $_ } } (0..$#array);
    
}

[download]
Return : 
        0     1     2     3     4     5
peach   2982  3026  2010  1095  573   314
banana  2961  2973  1960  1172  602   332
mango   1996  2004  2333  1866  1100  701
orange  1156  1116  1914  2558  1999  1257
apple   602   561   1162  2030  3171  2474
cherry  303   320   621   1279  2555  4922

[download]
Not really randomized huh ? ...

In reply to Re: help in understanding the standard array shuffle by Gloom
in thread help in understanding the standard array shuffle by Anonymous Monk

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