FMList.io is a free site that aims to convert tab angst into motivation.
You simply need to visit the site, and enter a task. Click on the "+" sign, or press return; then prepare to be annoyed.
Instead of presenting a task list in the traditional manner, the site creates a new tab for each task, complete with the tab name reflecting the task you've entered. The goal here is to force you to address your to-do list by putting it directly in front of your face while you surf the Web. It's too easy to find yourself wasting two-hours on Reddit reading a ELI5 thread and learning. But when you have a tab open with the title of what you should really be working on, you may just get some real work done.
Thankfully, checking the box next to a task will close the tab, thus providing motivation for you to get to work.
The team behind this super-duper annoying site is also behind a fun iMessage prank that used an animated image to trick your friend into thinking you were forever typing. The team also created a clever workaround for arranging the icons on your iOS home screen however you'd like (as opposed to sticking to Apple's grid layout).