SHIMODA Hiroshi has created Split Browser, an add-on for Firefox which lets you split the content area of the browser window as you like.

You can split the window infinitely, as many as your RAM and your screen allow.

Firefox Split Browser - Also good for getting splitting headaches!

There are a few ways to split the window:

• Choose the “Split Browser to” menu in the context menu
• Choose the “Load in Split Browser” menu in the context menu on link
• Click popup-button on top/bottom/left/right edges of the content area
• Drop links, bookmarks, etc. to popup-button on top/bottom/left/right edges of the content area while dragging

The status of split browsers are saved, and automatically restored on the next startup.

Visit the Split Browser add-on page for more information and a link to download the latest version.

Link via Hongkiat