$g ='* * * * * Just  another  Perl  hacker. * * * * *';;$t=length$g;
sub h{select$9,$8,$7,pop}$|++;;$r="\r".' 'x$t;;print$g;h(1);{h(.15);
print"$r\r@{[' 'x(($t-length$g)/2)]}$g";do{die"$r\n"}unless$g=~s|(.)
(.)|($1,$2)[rand(2)]|gex;redo}