A 2002 game that has far more gameplay focus than graphical. Fun and thoughtful. It's a 'true' hacker game in that most of the puzzles are randomly generated so you can't just consult a walkthrough.
The learning curve is harsh as one serious mistake unrecoverably ends the game. Slow and steady and cover your tracks.
There's enough to do for quite awhile to keep you entertained, though there are only about 10 or so mission types. The end and only story is a series of mission played for either ARC or Arunmor.
All in all I had a lot of fun with it, though the interface leaves a LOT to be desired (rarely does tab focusing textt fields work. Shift tab opens the Steam overlay instead of going back, and most textfields can only have text entered when the mouse is hovering over them. Even so: fun.
The game does have the support of a small mod community, so many missions and upgrades have been added to rectify a lot of these issues.

Phenomenal 2-4 player co-op shooter. It's literally L4D without zombies, but with hundreds of cops ready and willing to put lead and tasers into you at range.