Hi there!
Have you ever find yourself too lazy to open codeforces, find a problem and start solving it, even if you have free 10 minutes? I have. All the time. This isn't something I'm proud of, and I decided to motivate myself somehow, therefore I created a chrome extension which allows you to select a random unsolved problem in a single click.
To make things interesting, it also starts a timer, so you can practice solving tasks faster. And if you're lucky enough to solve the problem in time, you'll receive a special gift — notification!
You can download the extension here: Chrome Extensions Store.
This is a beta, so your feature requests and bug reports are very welcome here: Github