Local and session storage are a great way to store data without resorting to cookies. IE8 supported
sessionStorage so you may not need a polyfill. If you do, Remy's is a piece of cake to implement and use.
This is a simple key/value store, so if you want to store complex data use
JSON.stringify(obj) on your way in and out. There is also no way to know if you exceeded the storage cross-browser, so wrap your store commands in try/catch. Up to 2.5MB is safe to use.