I thought I had seen something about this but didn't really pay it any heed - then started, and yeah, I really like it.
Pretty easy to use as you can see. Just bring up Chrome and hit the tabs button to see all the tabs you have open, then just long press it and drag it onto any others you like to have them joined with.
Just like you would for any app icons in your launcher/homescreen
Interesting that it only works on Android, and you can't do the same for iOS.
So, organize away - tabs with shopping sites, tabs with news, etc... makes it easier to find if you're a guy like me who keeps a ton of tabs open all the time.