That is why you should be using a good firewall with HIPS.
As far as the NSA snooping, I could care less. I don't do anything illegal or immoral.
i've used them all, if these dudes are hacking banks what is that going to do? Actually short story, years back one christmas morning my pc fried, my pc started getting errors after a russian american friend of mine went to jail for credit card fraud, supposedly caught out of state with 72 cards in his pocket. I started talking on aim with one of his associates just to find out how he was doing, and my pc starting having problems.....after about a month on christmas morning my pc went off and never went back on again. burnt mobo and vid card. It felt personal, but was probably also a combination of covering their tracks.
The reason why I would never believe it was the secret service or NSA or FBI, is because they would not fry my pc, they would keep milking it for info as long as possible.
Nowadays its not about prevention, its about detection... assume your already hacked.