Overflows w/o overflow box

[Briguy350]

Im upgrading to a new tank soon and have been researching on what type of overflow to use. It will be a 125g. I've seen some bigger tanks online that don't have any overflow box at all just looks like 2 or 3 bulk heads right on the back of the glass. Do these have a specific name or style (herbie, durso, etc.) are there any pros or cons with these. I like the extra room you'd have and the clean look. Any info appreciated!

 

[Reefing Madness]

The Herbie and the Bean Animal are a bit more on the safer side than the overflow boxes themselves.
BeanAnimal's Bar and Grill - Silent and Fail-Safe Overflow System
Glass Reef - The Basics - Overflow

 

[DO NOT PM]

Herbie would be a challenge without an overflow box. You can do an external durso if you want to go with the bulkheads on the back of the tank. If you can find them, bulkhead screens like this are awesome for such a purpose:

http://thespaworks.com/sites/thespaworks.com/files/imagecache/product_list/wwp640-3257v_2.jpg