Skeleton Key

Origin
Skeleton key was created in 2080 as the planet was being rebuilt after the unification war. The creators of the Skeleton key helped create the new dark net which is essentially the 'underground' as tech savy web surfers know of it as. The SK at the time was the only way to connect directly to the underground, sometime at the early 100s the SK was discontinued and the creators went under the radar.

Application
The SK connects via USB to a laptop or desktop, it will boot up virtual machine which will run the basic programs to get into the underground of the internet. Chat rooms, sites and the sort. Functions such as hacking or breaking code, mining data and the sort are out of the question as the SK was made just to connect to others covertly and more easily. The only downside is the lack of features outside of connecting. Most modern day terror groups possess one SK or a hacker.

Other methods
Without a SK there are still ways to get into the dark net / under ground of the internet. You may need to hire a hacker or teach yourself how to get past the government bypass and into the specific areas of interests. A skilled hacker will be able to contact, communicate and interact a lot better with groups and people operating in the underground than one would with a SK. That being said a trustworthy adept hacker are hard to come by in times such as these.