I tried gmail, yahoo, aol. But they are not the best for automation. Gmail needs SMS many times and some times it just gets picky and doesn't allow you to sign up automatically(captcha entered manually ofcourse). Whenever I try to automate yahoo signup process, it just doesn't work. It completes whole signup process and after the bot clicks signup it just goes to the yahoo home page. weird. aol works well. except it is pretty difficult to automate. because its ajax interface keeps changing and is difficult to work with a bot. its difficult to click links inside a mail in the inbox. So have you tried to automate the signup and email checking process in any free email services. Did you have success with anything? Is there anything that you suggest?