Hello,
I’m working on some clusters. At some point I’ll share them with other people but I don’t want them to see what’s inside. I’ll set a password for the cluster but I wonder if they can find some other way to see what’s inside. Doing something outside the Rhino and GH environment, I mean? Does anybody have any knowledge about it?
It is very easy to see the password for a novice programmer, it is a false sense of security. If the people you are sharing it with are clueless about any kind of programming then it should be fine. I wouldn’t put anything in there though that you are very concerned about someone peeking at. A better solution would be to code it and then obfuscate that code. People will always find a way in, if you care enough then most you can do is make it really annoying to read 
Do you mean coding what you do with the components in a GHPython component?
To write the components you want to make and compile (c#, vb) instead of making clusters this way you can obfuscate the code in case someone breaks in they will have a hard time reading it.
It’s quite easy to decompile any .NET-based program, though the obfuscation might be difficult to go through. The most secured way would be wrapping your core logic inside a native library, guard it with heavy-duty tool (such as VMProtect) and P/Invoke it. However, I don’t believe the protection would turn out to be worthwhile.