Digital Sky Technologies (aka DST), the Russian Internet holding company that holds stakes in several major Russian-language social networking and communication players and notably also recently invested in Facebook , is melting two of its largest portfolio companies together into one online powerhouse. Astrum Online Entertainment , itself formed by DST after merging five online game companies that were active mainly in Russia and Eastern Europe (Astrum Nival, Nikita.Online, IT Territory, TimeZero and DJ Games) back in 2007, will effectively become 100% owned by Mail.ru , the leading Internet portal in the Russian speaking world and equally majority-owned by DST.