Our department has a department site as part of our larger company SharePoint site. We've created a task list on the department site, and we want a large group of people from multiple departments to be able to view and add tasks to the list, but without giving them access to anything else on our site.
- Uninherit the list
- Give access to whoever needs it. If it's a large group I suggest using an AD security group.
- Give them the direct link or post the link elsewhere that they can navigate to it. They will not be able to navigate to the site that it's hosted on.