Dive Summary: 

• Serbian architects proposed a design for underwater trash and recycling facilities to convert the 3.5 million tons of garbage floating in the Pacific Ocean to energy. 
• The underwater structures would consist of garbage collectors, a recycling plant, housing units and recreational facilities. 
• The idea received an honorable mention at the 2011 eVolo Skyscraper Competition. 

From the article: 

Looking at a picture of the Great Pacific Garbage Patch gives one the urge to fashion a huge pool skimmer, hire a boat, and lift all that trash right out of the ocean. 

Apparently it's not that easy, and even if you could skim it all out, there's no way to keep another patch from forming. That's why a team of Serbian architects devices a series of underwater skyscrapers that could be placed in the gyre, ready to collect all the trash and convert it into energy. ...