I have been a irregular blogger for some time. So my earnings got way below my previous earnings but what was a life saver was Money4banners. One of my websites got accepted at the time i was regular and i got a 10 pound sign up bonus. What's in return to putting ads at only one three pages i got 10 pound monthly. This wasn't a considerable amount but when my sites became dormant and didn't earn much(cause of my irregularities) i got 10 pounds monthly just by putting the ads and nothing else.
Money4banners has worked like a charm for those sites which didn't earn much by pay-per-click and pay-per-impression ads.
And you get 10 pounds for every domain you get approved.
The various terms and the implemented versions of the ads can be seen in my previous post