What concepts, practices and technologies can help manage landfills more sustainably?

Landfills are an eyesore, and they can be a lot more than that to those who are living nearby. Most cities in the world are struggling to maintain their overflowing landfills. At the same time, landfills contain a lot of value - be it organic matter or useful recyclable materials. Landfills also give out landfill gas, which can be used as a heating fuel. With such potential, how sustainably can landfills be managed so that the twin benefits of waste management and value recovery can be enhanced?

Questions