Login check

[eluser]Werner85[/eluser]
Hello.

In the application I am building I need to check if a user is logged in. Currently I am doing this by extending the Core Controller.
Every controller I create now extends MY_Controller.

But I was thinking: Can't I put this Login check into a Library, Helper or Plugin?
This way I can use the default "extends Controller" again. Which is a lot easier...

Can anyone tell me which way is correct?