3. Porno - Danny Boyle
The Movie: An adaptation of Irvine Welsh's novel Porno, a sequel to Trainspotting, which catches up with the characters from the original movie ten years later.
Why It Hasn't Been Made: Boyle has expressed a wish to direct the sequel, and was waiting until the actors had aged adequately to suit the passage of time...which they most certainly have by now. Though Ewan McGregor was a question mark for a while, given his very public falling out with Boyle - because Boyle apparently promised him the lead role in The Beach, and then gave it to Leonardo DiCaprio - but he's recently said that he's more than up for reprising his role. However, Boyle has admitted that it's "not a great book in the way that Trainspotting, the original novel, is genuinely a masterpiece", even if he maintains that a 2016 release is likely. Still, given that Boyle has a knack for pushing projects back - as happens constantly with 28 Months Later - there's no point holding your breath for this one.