868-HACK is an unusual sort of puzzle hacking game that feels a bit like an old school roguelike. Created by Michael Brough, author of Corrypt and Zaga-33, the game puts you in the happy shoes of a happy computer hacker bent on stealing precious data in the night. By swiping across grids filled with siphons, resources and enemies, you can walk away with all the data while setting an impressive score for your run.
A cinematic simulation of hacking that owes more to Wargames and Sneakers than Kevin Mitnick and Adrian Lamo, Uplink: Hacker Elitecyberpunk intrigue. Originally released by Introversion Software in 2001, and streamlined into the Hacker Elite version for the US market, the latter is now available for purchase from the lovely indie and retro game outlet GOG, and it's a worthy addition to any gamers library.
In the browser-based HTML game, Slave Hack, you take on the role of a vaguely tech-savvy Internet addict who has now decided to make a living out of his/her own talents. If your ethics do not prevent you from pretending to infiltrate other computers to use them as spam relays, warez-sharing nodes, or even as tools to bring down an enemy's computer with a massive DDoS attack, then you are excellent material for the world that is portrayed in Slave Hack.
Cyberpunk is a simple Flash puzzle game disguised as an arresting and involving hacking simulation. Armed with four programs and some intuition, you'll have to sneak into a remote computer guarded by obscure (and not-so-obscure) passwords, as well as by some nasty puzzles.