rokkolpo said:
When you ask people to outsmart your younger brother, you have already lost.
This is completely true.
However, there are several things you could do. Firstly, let's think about exactly what your problem is: Your little brother is threatening you with an ability to disable something you like. Let's treat it like a weapon scenario. Person A threatens person B (that's you) with a secret device capable of damagin/destroying/disabling something person B likes, potentially so they can use this to influence person B. To stop this, there are a few steps:
1: Disable device - Find out what it is he plans to use to do this, and stop it from being able
to perform that function. It may be a private computer. In which case confiscating it, or removing the software capable of performing that function solves the problem. Infecting the computer would work too but i'm not going to reccomend or condone that.
2: Disable system - If this can be done with the internet as he hinted, remove his ability to access the internet. Be inventive.
3: Counter threat with Mutual assured destruction. Find something he likes, find a way to take it from him and threaten him with it if he uses his device
Any of the above three will work, hope i've been of service.