On one of my mainstream sites, I notice that generally 40% of my uniques arrive there without any referrer at all. I'm highly doubting this is returning bookmark traffic because it's a site that is never updated and it's not any type of service you can use (unless you signup which the signup has been down for 2+ months).
www.healthygo.com is the site btw...
So what I'm wondering is, where is this traffic coming from? The only logical explenation I can think of is for some reason (due to browser / os configurations possibly) referrers aren't being sent, or it's from various spiders etc... But I average about 60 / 80 uniques a day without referrers.
I've also done no other advertising aside from the net.