A lot of people here have suggested AMR, as it should be expected. The problem I have with AMR is that it's becoming impossible to create a good list for submitting. Most people that use AMR also use Scrapebox which basically meas that most of the directories have already been found and spammed to death.
I won't discuss the effectiveness of AMR because I haven't used it for a while so I don't know what the current status it but when I left it off that was a major problem.
This isn't really a problem with AMR though, it's a problem of quantity vs quality. If you want to submit to quality directories there will always be a choice, but if you rather just want to submit spam and count on numbers your choices are limited because no matter how many directories are created as long as they're public they'll be spammed to death within a few months if not sooner.