Another Terminal Introduction for your pleasure.
Mary Norbury-Glaser offers an extensive 5 part insight into the, sometimes nerdy, details of the Mac OS X Terminal.
Even those who already judge themselves terminal-savy could try it as the later parts concentrate on the new features that came with Tiger.
Lingon is a welcome GUI tool which helps to edit the Launchd configuration files. Launchd is the a new system daemon in Tiger which starts all kinds of system processes during bootup (it’s the reason why Tiger boots _so_ much faster than previous OS X versions).
Launchd stores it’s configuration in Plist files, whose editing is not obvious to everyone.
Lingon simplifies this process to a great deal.
If you happen to use your Mac multiuser capabilities (= more than one person has an account on your mac) it probably already happened that there were files which all users should access, or directories where everyone should be able to write to but not delete from. OSXFaq now has a nice tutorial covering everything User/Group/Permission in OSX. It requires a fair bit of terminal (bash) knowledge, but gives you a lot of new capabilities in return.
It even mentions so-called immutable files, which can’t be deleted by normal users nor root (this alone should give you 15 ideas on how to play a trick on someone ;) )
Read it here