Best Website Statistics tool for Drupal

Question

What is the best free Website statistics setup I can have for Drupal 6 on Apache? Particularities: 1. Multisite install. Might want to look over several sites. Should be able to restrict view for clients to their own site.

1. Some hits are bypassing Drupal.

2. Some urls are not public.

3. Some sites have little traffic, it would be nice to be able to exclude "own" traffic.

4. Logged in users are not so important

(It seems Google Analytics is popular)

Answer 1

Google Analytics. THere is a module for it that does everything you asked.

http://drupal.org/project/google_analytics

Answer 2

There are several statistic modules for drupal, but it depends of what do you mean by "free" :-)

free as "free beer"? Google Analytics is simply the best.
free as "free speech"? Give a try to Piwik.