As we all know, OS X is a Unix-based platform for which the subject of permissions is no superfluous matter. Remember all those non Apple kexts that, at some point in time, required forced entry into /System/Library/Extensions? All those community released installers? I'm not saying that the community releases are evil but just stating the fact that all these touch the OS X file system and with that comes the probability disturbance of the file system permissions or "access privileges".
It's a good thing though that utilities to accomplish this maintenance task are readily available. One of which already comes installed by default on Macs and hackintoshes alike.
Enter Disk Utility:
Permission errors, though seemingly trivial, can indeed cause a large number of problems - from applications not launching, to slowing OS X's performance to much serious ones such as the OS not being able to boot up at all.
Also, still related to kext installation, it would be beneficial to run utilities that take care of system caches. Since the combination of kexts is crucial for a hackintosh to boot up properly and system caches are very involved in that boot up process, this maintenance task is all the more essential.
You can use Onyx (for Snow Leopard) to clear the system caches.
You can also repair disk permissions via this very same app, and other similar maintenance related tasks, which Onyx one very convenient app.
You'd be amazed how much better your Mini MacBook responses after doing these seemingly insignificant maintenance activities.