A Lesson on Spelling and Pronunciation.

Legally, (in the U.S.) you can name your kid anything you want. DO NOT NAME YOUR KID ANYTHING YOU WANT!
What you name your child will be with him or her for the rest of its life. A name is like a tattoo that you don't even get to choose yourself. This is not the time to be super creative. Be a little creative, but hold back a bit.

One place you don't need to be creative is the spelling. Taking a classic name and putting your own spin on it will not make your child stand out, nor will it do him any favors. Take alternative spellings of Brittany for example:
Bretteny, Brettney, Bridney, Britani, Britanny, Britianee, Britney, Brittainy, Brittney, Bryttany, Bryttnee.  And the list goes on. 

What is little Britianee going to do when she gets to kindergarten and starts to learn how to spell and read? By the time she reaches high school, she is going to hate having to explain that her name is
Brittany with an 'ian' and two 'e's.  You're naming a child, not trying to get rid of extra tiles at scrabble.

My wife, working with youth, has encountered a fair amount of unfortunate names. There was a girl named Anastasiaah, which was spelled that way because the mother thought it looked prettier..  The worst example of irresponsible naming was a young boy named Bat.  Why would someone name their child Bat? (You may have guessed) It was because his last name was Mann. Some parent named their child Bat Mann. He was planning on changing it on his 18th birthday.

Many other countries have naming laws.  Some have an extensive list of approved names and spellings, others say that the name cannot unduly harm the child. I do not anticipate any laws like that being introduced in the US. However, I hope parents would be more responsible.

Update: Since posting this, a number of people have posted comments about other names they've encountered. I looked into them:

Abcde - This is apparently a real thing. Pronounced "ab si day"

Shithead - Pronounced shih theed, I haven't since a good source on this one. However, it seems to be a common Arabic name that parents don't realize the other spelling.