Yahoo's YPN ads are a good alternative to adsense. It might not come with aggressive payouts but it is popular and running well. YPN is the second most seen ads on Internet pages. It has a very large network and has its own "adword" network for your publicity campaign.

Yesterday I saw a post in Digital Point forum . A person claimed that he is gettiong upto 3 $ per click in YPN.

Bidvertiser is better choice . You need to reach only 10$ earnings to get paid.
In adsense you will get paid when your balance reaches 100$

There are many alternatives to google adsense like bidvertiser, axil, ad space, cBproads, ads for Indians. You can choose any of them.