Help me understand gamertags

Having played quite a bit of the multiplayer component in Black Ops I've come across some odd, weird and quite frankly absurd gamer tags, all I ask of you GB community is to decipher and explain to me what these gamer tags mean, the thought process behind them and help me understand online handles. I won't use full gamer tags but some parts of the gamer tag that has stuck with me: 
 

• iTz - at first I thought this was a local clan but I've seen plenty of people using this, perhaps the clan is huge I have no idea.
• xXx - this is usually placed at the beginning and/or end of each gamertag, I can kind see how it would be if a particular handle wasn't available at the time but surely that's attempting to encourage the user to pick another name?
• qUiCkScOpEz - Two things here, I've never been so sure as to why people alternate the letters in gamer tags, it takes a bit more time for me to read it properly and... well it just looks a bit silly. Also the handle "Quick Scopes", I'm quite curious to why the S is replaced by a Z.
• Magic, Fusion, Killah - Of course these names are usually mixed up with alternating letters and are usually accompanied by a variation of O's, I's, L's, X's and what have you. I'd quite like to know the origins of these.
• 243958235 - Lots and lots of numbers, at first I genuinely thought that somebody put their phone number in their online name but as it turned out it was just a string of what I assumed to be meaningless numbers. Having spoke to someone with a gamer tag like this I didn't get any further to why this is so popular. 
• Qu1ck5c0p3z - Numbers replacing letters, this one just blows my mind. I've seen plenty of perfectly good names online only to be butchered by replacing some letters with numbers. What the hell?
• A specific year - 2006, 2K7. For Steam this is fine, you don't get charged to change your name. But for something like Xbox Live where it actually costs you change your name? Surely you'd want to bypass this problem and leave out years all together? All of this is assuming you don't want the gamertag "quIcKSnipEZ 2k8" in the year 2011.

Anyone who references anything to do with sniping in their tag is pretty much always a dickhead online.

lol, are you serious? 
 
It's just people being dumbasses. None of that "means" anything.

I'm guilty of having two X's in my GamerTag. I'm sorry if I have offended you.

In games like Quake (the original) with text kill-notices, some names just fell into place that otherwise seemed odd. For instance:
 
Theman was killed by A 7 YEAR OLD GIRL
 
Theman ate HIS OWN MOM's boomstick
 
Theman rode HIS DADDY's rocket.
 
Then someone figured out how to do animated names in the Quake engine...I think the program was called 'Name Fun'. When this came out is when I first noticed people using XXXxxxXXX and such in their names, but of course it was animated. And annoying. After that the clusterfuck began, and now that shit just doesn't make any sense.

With the numbers: I think some people do this just to get online, they look for a quick solution so it might be a mix of DOB, some phone number digits or a number that they can remember or work out easily when they log on. Useful for gamers who play cross platform or with multiple accounts.
 
Mixing caps and lowercase changes the shape of the word making it easier for the owner to spot their tag in a list of names on a screen, shape sHaPe or sHAPe and addiing symbols or numbers is all part of that l337 or l33t or leet speak world.

All that is just peoples personal preferences. Besides, what does it matter? You'll never talk to the majority of players with those types of tags anyway. I don't. I'm also a bit anti-social tho. 

" Anyone who references anything to do with sniping in their tag is pretty much always a dickhead online. "

You're worrying about things you shouldn't give any thought.
 
Most people are just crazies and think having such tags make them cool :O

Dude, I've had Kaos Angel as my PC ID since the late 90s, to this date I still have no idea how I came up with it nor do I know what the fuck it means. 

The thing is there really isn't much of a thought process behind most of these. I can tell you for a fact every time someone has put most of those components into their name there was no greater meaning behind them than "This looks really cool", or "It's what all my friends are doing".

iTz can mean two things: In The Zone, and just "it's". Basically, it is a stupid little prefix kids use on their Gamertags to make them more unique. Or something. People use an 'x' on their name to break it up. That's my reasoning at least for the usage of the letter in my name. I never see multiple x's, unless someone is really, really unoriginal. Quickscoping is a method of playing Call of Duty online that is highly ineffective, but is far and away one of the most popular pastimes for those who have a voice that shatters glass. Magic, and all of those words are basically used because of the presence of the letter 'i'. 'Fusion' doesn't sound original, but 'FuZiioN'? Much more zany. The trivial numbers and years basically are there for people who cannot come up with something original. I love your name of Berezov, but if it's taken, one can simply take 'Berezov 2k10' or 'Berezov249290'. Normally those numbers are in a sequence though, such as 2, 4, 6, 8 and so on. 
 
Basically, I know enough about those Gamertags to move in the other direction when I see them coming. Most of them are from younger kiddies who will yell obscenities down the mic. I prefer taking my headset off. ;)

Simple answer: All the good tags are taken so the only thing you can do is try to mimic it by adding extra letters or numbers.

iTz

xXx

quickscopez

Magic, Fusion, Killah

random numbers

Numbers replacing letters

Specifc year

I have my birthyear in my gamertag and I hate it, but there is no way i'm paying 800 points to change it.

" Dude, I've had Kaos Angel as my PC ID since the late 90s, to this date I still have no idea how I came up with it nor do I know what the fuck it means.  "

• "iTz - at first I thought this was a local clan but I've seen plenty of people using this, perhaps the clan is huge I have no idea.

• xXx - this is usually placed at the beginning and/or end of each gamertag, I can kind see how it would be if a particular handle wasn't available at the time but surely that's attempting to encourage the user to pick another name?
• qUiCkScOpEz - Two things here, I've never been so sure as to why people alternate the letters in gamer tags, it takes a bit more time for me to read it properly and... well it just looks a bit silly. Also the handle "Quick Scopes", I'm quite curious to why the S is replaced by a Z.
• Magic, Fusion, Killah - Of course these names are usually mixed up with alternating letters and are usually accompanied by a variation of O's, I's, L's, X's and what have you. I'd quite like to know the origins of these.
• Qu1ck5c0p3z - Numbers replacing letters, this one just blows my mind. I've seen plenty of perfectly good names online only to be butchered by replacing some letters with numbers. What the hell?