Google Bookmarks

I was first introduced to online bookmarks in middle school with a service I think was called Emu Mail or something... anyhow you could store web-addresses from anywhere. Google has bookmarks that you can access either with its toolbar for IE/Firefox or through Google Notebook online.

Google bookmarks are organized with labels, much like in Gmail. But unlike your browser's bookmarks or favorites, you can't have a sub-labels like you can have sub-folders. But for Firefox there is an add-on that allows you to "hack" sub-labels into Google Bookmarks. --> Gmarks.