Call a Mathematica program from the command line, with command-line args, stdin, stdout, and stderr

If you have Mathematica code in foo.m, Mathematica can be invoked with -noprompt and with -initfile foo.m (or -run "<<foo.m") and the command line arguments are available in $CommandLine (with extra junk in there) but is there a way to just have some mathematica code like

#!/usr/bin/env MathKernel
x = 2+2;
Print[x];
Print["There were ", Length[ARGV], " args passed in on the command line."];
linesFromStdin = readList[];
etc.

and chmod it executable and run it? In other words, how does one use Mathematica like any other scripting language (Perl, Python, Ruby, etc)?