Have you seen Trainspotting yet? I have and I must say that it's unquestionably one of the best movies EVER! If you haven't seen Trainspotting yet, then you're missing out and you should DEFINITELY watch it! It doesn't REALLY take you long to realise that this film is UNDENIABLY one of the finest portrayals of the junkies world.
By the way I have also read the book Trainspotting written by Irvine Welsh (the movie is based on this book!) and it was thoroughly awesome!!!