Highly sophisticated malware isn't limited to relatively high-profile sabotage code like Stuxnet -- sometimes, it's designed to fly well under the radar. Symantec has discovered Regin, a very complex trojan that has been spying on everyone from governments to individuals since at least 2008. The malware is highly modular, letting its users customize their attacks depending on whether they need to remote control a system, get screenshots or watch network traffic. More importantly, it's uncannily good at covering its tracks. Regin is encrypted in multiple stages, making it hard to know what's happening unless you capture every stage; it even has tools to fight forensics, and it can use alternative encryption in a pinch. Researchers at Symantec suspect that the trojan is a government-created surveillance tool, since it likely took "months, if not years" to create.