Chrome Extensions: What's on Your Browser?

I recently started exploring the wide range of extensions in the Chrome store. So far I've landed on three that I actually use regularly.

As a Kindle owner I've found the Send to Kindle extensions really useful. Especially when I come across lengthy articles that I don't want to read on a computer screen. It works pretty seamlessly and formats well (about 90% of the time).

I've also gotten into Evernote after much hesitation. Ha funny that I joined on the heels of this massive password reset. Thankfully I had nothing compromising on there. I write a lot of stories and Evernote has been really helpful in indexing sites for research.

The third extension I use is the any.DO extension. I was using Apple Reminders before that. It's great that Reminders is integrated across the OSX and iOS via iCloud. Yes, you can access your iCloud services in a web page but having that little any.DO extension is less obtrusive and better integrated IMO.

What do you use for productivity, entertainment, or otherwise augment your browsing experience?

Also, what isn't available that you wish was? OR could be better?