Can't Get Apache To Start - No Errors!

Up until yesterday I was a happy Apache user on Debian unstable.  But the
other day (according to the syslog) Apache was killed for memory reasons.
 Now it won't start!

I run /etc/init.d/apache start, and it says all the things it used to, no
errors, but doesn't actually start.  /var/run/apache.pid changes every
time so I know a process is at least being started, but by the time I can
check, it's already dead and gone.  I've checked /var/log/error.log and
can't find anything that seems relevant in there (only the messages I get
when Apache is starting).  I would really like to get my webserver back
up - can someone help me?

-Kurt