Domain Manager is an application designed to organize your domain names, hosting plans, and many other related things.
If you let Domain Manager access your calendar, it can also create events to remind you when your domains and hosting plans expire. You can also create tags with custom names and color that you can then assign to any domain, hosting plan, owner or provider in case you would like to create your own classification system. The application also makes it easy to filter your entries based on tags, owners, providers, etc.