Instead of Boomerang, check out Gmelius. It’s a similar tool with more features and it changed how I use Google Mail.
Honey is awesome and so is WikiBuy (a more recent discovery).
If you’re a reader, Panda is awesome coupled with Instapaper.
Used Momentum for months, then read about Leoh! in the comments here. Replaced Momentum with it.
Awesome Screenshot it a great tool, also recommend Eye Dropper for color selection. Sometimes I love a website’s color variation and like to save the # values for my own reference later. Lastly, on the techie side, EditThisCookie is a fast way to clear specific cached singular website data without clearing the whole browser, VERY handy when you’re only having issues with one website and don’t want to nuke the browser.
Grammarly is a great recommendation. I bought the premium version a while ago and it’s been nothing less than terrific.