The Nostrand Avenue building where Sergeny Mamontov chopped up his roommate, Aleksandr Zilbergleyt. Source: Google MapsSergey Mamontov, the 50-year-old lunatic who brutally [/horrid-testimony-from-sergey-mamontov-in-roommate-slaying-case/] butchered [/sergey-mamontov-found-guilty-of-gruesome-roommate-murder/] his 55-year-old roommate Aleksandr Zilbergleyt received a 25 years to life sentence on Monday. The New York Daily News reported [http://www.nydailynews.com/new-york/