Proof - Website conversion rate optimization and visitor monitoring

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

Fomo - Fomo turns your site into the online equivalent of a busy store

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.

OptinMonster - OptinMonster helps to convert abandoning website visitors into subscribers and customers.

Strikethru - Strikethru is a kind of to-do list notebook for managing work lists and staying updated with the important tasks.