What's the best way to send ALL incoming mail to /dev/null using postfix?

I'm testing something, and I need to send about 900,000 messages to this box
and throw them all away, and then view the logs to find out exactly how many
came through.  I figured out how to reject incoming mail, but I don't want
to bounce it, I want to accept it all and put it in /dev/null.  The To:
addresses are thousands of different domains also.

Jay