Blokada - The best ad blocker for Android. Free and open source.
BlockParty - Real-time voice chat rooms from the creators of turntable.fm
AdBlock - Ad blocker for Chrome, Safari and Opera on desktop and Safari for iOS devices.
Secateur - Use Secateur if you want to temporarily or permanently block or mute (or both block and mute) a Twitter account and all its followers.
AdGuard - Surf the Web Ad-Free and Safely. Shield up!
Boyfairy - Your opportunity to educate right before you block someone.