2000 A.D., aka Gong Yuan, is one of the all-time great hacker movies of all time, featuring a great scene where a super-elite cyberwarfare program crashes the Stock Exchange by deleting Windows folders. Which is then followed by awesome kung-fu.
Actually, my favorite scene is the one above, where someone explains that future wars will be fought with "cyber-bombs," and a single laptop computer can do more damage than an atomic bomb. Not to mention, the casualties of cyber-warfare are "already very high."
But below is the scene where they crash the Stock Exchange (at around 30 seconds in) and then the absolutely brilliant kung-fu battle starts about six minutes in.