Now another category is DATA Destruction Trojans. These kinds of trojans are quite simlar to RATs, but the purpose of these trojans are little deifferent. They also send the data to remote locations, but after sending this data to remote locations, they do damage the data on local machine and then later on, hacker can ask you to pay the price for data. Or sometimes, these trojans don't destroy the data, but encrypt them. Again, hacker may contact you to ask some money to decrypt your data. This is again cyber crime. Few years ago, there were many such cases where hackers demanded the money to give back the data to companies. These kinds of HACKERS target companies, instead of individual users most of the time.
To detect such trojans on your machine you have to adopt the same way as used for RATs. Moreover you can use some third party softwares to protect your personal files.