Actually, I tried to patch Data::PowerSet with an option to create adjacent output only:

$ diff -ubB PowerSet.pm.org PowerSet.pm 
--- PowerSet.pm.org    2008-05-30 11:22:31.000000000 +0200
+++ PowerSet.pm    2008-05-30 12:46:32.000000000 +0200
@@ -9,7 +9,7 @@
 use Exporter;
 
 use vars qw/$VERSION @ISA @EXPORT_OK/;
-$VERSION = '0.05';
+$VERSION = '0.06';
 @ISA     = ('Exporter');
 
 =head1 NAME
@@ -18,8 +18,8 @@
 
 =head1 VERSION
 
-This document describes version 0.05 of Data::PowerSet, released
-2008-05-13.
+This document describes version 0.06 of Data::PowerSet, released
+2008-05-30.
 
 =head1 SYNOPSIS
 
@@ -161,6 +161,22 @@
 When this attribute is used, the C<next()> method will
 return a scalar rather than a reference to an array.
 
+=item B<adjacent>
+
+When this attribute is used, the returned list will contain adjacent
+elements only. E.g. 
+
+  my $ps = Data::PowerSet->new( {min=>3, adjacent=>1}, 2, 3, 5, 8, 11
+ );
+
+will produce
+
+  2, 3, 5, 8, 11
+  2, 3, 5, 8
+  3, 5, 8, 11
+  2, 3, 5
+  3, 5, 8
+  5, 8, 11
+
 =back
 
 =cut
@@ -195,6 +211,13 @@
 
     ($args{min}, $args{max}) = ($args{max}, $args{min})
         if $args{max} < $args{min};
+
+    $args{adjacent} =
+            exists $args{adjacent}
+                ? $args{adjacent} 
+                : 0
+        ;
+
     return bless \%args, $class;
 }
 
@@ -217,9 +240,18 @@
         return undef unless $self->{current} >= 0;
         my $mask   = $self->{current}--;
         my $offset = 0;
+                my $last   = -1;
         @set = ();
         while( $mask ) {
+                    if ($self->{adjacent}) {
+                        if ($mask & 1 && (($offset-1 == $last) || sca
+lar(@set) == 0)) {
+                            $last = $offset;
+                            push @set, $self->{data}[$offset];
+                        }
+                    } else {
             push @set, $self->{data}[$offset] if $mask & 1;
+                    }
+
             $mask >>= 1;
             ++$offset;
         }
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However, it produces one element twice, and I can't figure out why.