If you visit many different programming sites and come across problems you'd like to solve later, and forget about them later, consider giving this chrome extension :
Upsolve tracker a try.

See snapshots here and here.

Upsolve tracker lets you 1. mark problems for solving later across various sites

1. also lets you add tags to the saved problems

2. view your pending and solved problems at-a-glance in your dashboard

3. reminds you the number of pending problems via a badge on the extension icon.

More features such as activity graph and alarm reminder are in the pipeline.

Suggestions/ Pull requests at github repo are welcome!