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Don't expect fantastic graphics. The layout is very simple and very effective, although when enough servers come available on the world map it can get cluttered, but it's easy to tidy them up.
The game is addictive beyond belief in it's simplicity. Once you master how to hack into the systems and run the jobs, you tends to start to wonder - could I have done it faster, is there a better way, are there things that the game designers AREN'T telling me, what happens if I hack into here. There's nothing that gets the adreneline flowing faster than deliberately making a short number of hops to a server you know is going to be difficult and racing against the system administrator to complete your mission whilst he tries to run a trace back to your machine to find out who you are and shut you down.
The storyline missions are varied as well, do you take the side of the company trying to destroy the deadliest of computer viruses, or do you take the side of the virus writers themselves.
There are hidden servers, treats and plots within the game as well for you to try and hack, even a zipped file on the disk requires hacking to get at it's secrets.
If you like espionage and fancy trying your hand at hacking (without the legal complications), then this game is a definite must.
I bought it because it looked different and I'd enjoyed games like Hacker on the Commodore 64. Even now I'm an expert at it, I still can't resist just running a few more missions, trying to push the envelope that little bit further.