I have been in the IT world for about 8 years now professionally. I have done mostly hardware/software support and network support with some administration. I have also done some web developement (very little) and I know some bits of various scripting languages. I consider myself a master of integration I suppose knowing a very broad base of information (i hate the term jack of all traits master of none) with probably my best quality is hardware repair. I can pretty much break down any computer screw for screw and replace any part first time with out a service manual. This is just because I kind have always been that guy that did it when someone else couldn't. Of course that is not the limit of my knowledge by any means, but it is kind of what I am known for. I replaced a main logic board in a rev2 G5 iMac this week, a hard drive in a G4 ibook, a server board in a Proliant G4 HP server, etc.
I also in the last two weeks wrote a shell script for our new zen imaging project for imaging over networks. It basically pulls up an option menu when you run maintenence mode after netbooting. So, now all our techs have to do is netboot and select what image they want by typing in a number and the rest is automated through bash commands in the script, pretty handy stuff. I wrote the basic script from scratch and then gave it to the guy in charge of imaging and he took over and made it a lot more robust.
I have set up a few networks on the side for small businesses, and dabbled with some entry level cisco stuff. I know pretty much nothing about cisco other than some basic set up and config stuff. It is very complicated at the core, but for the most part I get around just fine using what I know and using google.
The thing is, no one can know everything it is impossible, and IT managers aren't stupid either. Most of them have made their way up into a management position, and when you manage you no longer do the grunt tech work, you manage. My managers started out doing my job and move their way up. They may not keep up with every little technology, but if you explain something to them in tech jargin they totally understand.
Also managing tons of users and a large network is no easy task. There are multiple reasons why you don't let users install their own hardware like the person mentioning the network printer before hand. There are also tons of reasons they don't let users log in with admin rights. There is no need to, and security is always something to consider in these types of things. I am not going to list them all because I could fill pages of reasons why IT departments do this.
Degrees and Certs matter to an extent, but I have to agree that it is experience that matters most. I can tell you from my experience you can put any type of computer in front of me and I can get it fixed. Some things may take longer than others but there is nothing I can't fix (granted i have the OK to order parts). Certs do look good on a resume though, and some companies require them to be considered a partner, or self maintainer
