[billmalarky]

Lijit was the best alternative for me, and I went through a good 5-6 networks. However, their CPM's were significantly less than adsense. Their support is really good though and they do actually have control over their inventory unlike a lot of other ad networks I worked with (many networks claim to be able to block audible/video/popup malicious ads but still allow many to slip through). Technorati is decent I believe (only used them for about a month) but their ads must be served out of an iframe (so they can't be contextual - so less CPM) because their ad servers are so slow and they are page blocking.

[Ryan_Jones]

I still use Lijit for their "backup ads" feature. Basically, I monitor the CPMs I'm getting from other networks, then set my floor CPM in Lijit to that number. That way, I get about 30% fill with Lijit - but it's guaranteed to be at a higher CPM than the other network. Chaining them together works really well - you just need to do it asynchronously so that it doesn't impact load times.