The Todoist Dropbox integration allows you to save files from your Dropbox account and attach them to tasks in Todoist. Simply clicking on the paperclip icon in the task comment field and choosing Dropbox will attach new files to the task.

If you forget the name of a file you've recently attached or a task you've been working on, you can use Dropbox's search feature to quickly find what you're looking for, or browse the files you've recently accessed.