Slicing two more characters off japhy and dragonchild's tie, I end up at 75:

print$"x--$h,qw(* 0 @ + =)[map$_?rand>$f?4:rand 4:0,$_..$_*3],$/for 0.
+.$h-1
[download]

Gotta love those slices :-)

I found that one while working on a non-destructive solution (not modifying $h and $f, that is).
I might as well include that ... 86 chars:

printf"%*s\n",$_+$h,join"",qw(* 0 @ + =)[map$_?rand>$f?4:rand 4:0,$_..
+$_*3]for 0..$h-1
[download]

The Sidhekin
print "Just another Perl ${\(trickster and hacker)},"