Edit; I know I am painting with some pretty broad strokes here- but I feel there are already a ton of threads all over the boards dedicated to the finer elements.
The types of chemistry sets popular in the mid-20th century have been banned for being too dangerous to children.
The democratically-elected governments of Turkey and Venezuela have effectively outlawed opposition parties from owning television, radio, and newspapers by alleging unpaid taxes in amounts that would bankrupt the companies if they paid, and having partisan judges hand their assets to the government. Media that echo the party line do not face these charges.
In the early 1990s, the Anti-Defamation League was caught using a private investigator to collect information on neo-Nazis. They were prosecuted and forced to stop collecting information on racists as a condition of a plea bargain. Collecting information on one's political opponents is now a standard practice of both the Democratic and Republican parties.
Your right to use a courtroom is being taken away. If you are lucky enough to have a job, did you read your contract? If it contains the word "arbitration", you have given up your right to sue your employer for any cause. They can decide not to pay you this month or demand sexual favours from you or your spouse, and you cannot take it to court. You can take it to a private, for-profit judge who is paid by your employer to rule in their favour, and they can order you to pay your employer's court fees for daring to challenge the situation. If you don't like it, you can quit; good luck finding a job in this economy. And people say there's no need for a union in the tech industry...
Specific to computer technology, the DMCA made it illegal to tell people how to crack access-control schemes. The two guys who cracked Cyber Patrol and published its list of blocked web sites were sued and had to surrender the copyright to their work. Warez and porn BBSes were shut down in the early 1990s; this is fairly equivalent to seeing warez sites shut down today.