No I dont run a blog farm i run a blog network of 3 sites! Blog farms are generally spam sites, full of useless content and thousands of links mine is quite the opposite!
I have only one blogspot and it is just 4 month old with 250 UV per day and made 22$ to 25$ per month.. I just update my blog once in 3 days or week and i never min abt traffic... Simply updating... And left alone
Yes, it is possible depend on how much your traffic and your ads placement. So far i make a simple blog which provide me $50~$100 per month even it is a low pay niche (game)
It is not too hard to earn good money from blogs . I am making $150+ from one free blog but my earning are little big because i have blogs on almost all niche . I will show you one blog which was on blogspot 2+ years and making adsense earning in 4 digits . Blog By Amit sir http://labnol.blogspot.com But now they moved to own domain and wp