There is a new ransomware called StalinLocker that will play the Soviet national anthem on your device, but will also delete the data on the hard drive it is installed on in 10 minutes if the user does not enter in the special code. Currently the code can be found by subtracting 30/12/1922 from the current date. If entered correctly and within the 10 minutes, the data will not be deleted, otherwise all connected drives will be wiped.
Ransomware is never good, but with only having 10 minutes to solve and enter the correct code, this particular ransomware is especially bad. Typically it is discouraged to turn off an infected device, but doing just that might save your data from being lost.