Use Alexa's comparison feature to compare wikipedia.org and google.com, they seem to mirror each other quite closely in terms of the sawtooth pattern.
I have no idea what it means, but it's worth noting.
Sunday, April 1, 2007, 11:47:07 AM, you wrote:
DRT> Looking at the Alexa stats for Wikipedia: DRT> http://www.alexa.com/data/details/traffic_details?q=&url=wikipedia.org
DRT> you see some interesting patterns. The graphs seem to have a DRT> sawtooth shape with a weekly period, but the specific days of the DRT> week where it peaks differ depending on whether you're looking at DRT> reach, traffic rank, or page views.
DRT> Can anybody venture any theories (original research!) about why this DRT> is the case?