http://steemtools.com/ (too much good stuff to list, just check it out)
http://steemit.deadfollowers.info/ (might help weed out followers who aren't active for you)
http://www.steemstyle.com/ (help style your posts)
http://steemistry.com/steemit-mentions-tool/ (a way to see if people mention you in comments)

:)