By storing data in the window.name property, you can store data between page loads and across domains without ever sending a cookie to a server. Thomas Frank created the sessvars.js library which makes use of this browser quirk, allowing you to store up to 2 MB of client-side session data.
This is really powerful for a few reasons:
- client-side, you can store way more data than allowed by traditional cookies
- none of the data is transferred explicitly to the server, minimizing bandwidth used for each page request
- allows you to talk between pages in different domains
Keep in mind that anything you store via this mechanism will be visible to any other site that a person visits, so this is best for storing non-sensitive data that you want to retain between page loads. This would be great for caching returned AJAX data that you would otherwise have to refetch and reprocess.