The address that Elliot (Rami Malek) searches on Google - 3027 W. 12th Street Brooklyn - is in fact the actual address of the building on Coney Island used for external shots of FSociety headquarters. (The broken "Fun Society" sign was added by the production.)
The pilot's title ("Hello Friend") is a reference to the email virus/worm GURONG.A from 2006. A feature of this worm is that it would send emails to everyone in your address book, often with the subject or first line "Hello Friend". The phrase continues to be used in spam, but the first virus to include the phrase made it "popular" in hacking circles.
Elliot (Rami Malek)'s use of CDRs to store the results of his hacks is similar to how real-life whistle blower Chelsea Manning stored the documents leaked to Wikileaks. Manning, a U.S. Army intelligence analyst, stored 91,000 sensitive military documents on a CDR labeled "Lady Gaga"; she was eventually convicted of espionage as a result of the theft and subsequent leak.
With an official broadcast date of June 24th, the pilot episode was released to On Demand almost a month before, to build online buzz about the show.
The opening shot pulls back to reveal a boardroom of "evil" people with a panoramic view featuring two skyscraper-construction cranes.
in the final scene, at least one of them is gone, suggesting that "construction is complete".