I developed this bot inspired by @klye's work.
This is a pure client-side javascript bot working on your browser, so you don't need to worry about exposing your private posting key to anyone. Check out source code here. It's only one html file. You can even run it on your own computer.
It will check your balance every single minute and claim your steem power if you have. Because this bot is working on your browser, it will be stopped if you close this page. You can keep it as one of opened tabs in your browser, if you want it to keep working on.
I wish this bot help you to enjoy your steemit life more.