Cracked Versions Still Possible
After seeing that cracked versions were no longer possible I decided to do some testing to see if this was completely true. What I came up with is a way to make a cracked version. Here is a step by step.
1. Login With A Legit Account and Run the Game
2. Go To %appdata%\.minecraft\versions\1.6.1
3. Make A Copy of 1.6.1-natives-(some long number)
4. Find "Running C:\somepath\javaw.exe..." on the Development Console of the Launcher and Copy That Entire Block Into Somewhere Like Notepad Where You Can Manipulate It
5. Change "-Djava.library.path=C:\Users\Zach\AppData\Roaming\.minecraft\versions\1.6.1\1.6.1-natives-(some long number)" to "-Djava.library.path=C:\Users\Zach\AppData\Roaming\.minecraft\versions\1.6.1\1.6.1-natives-(name of folder you copied earlier)"
7. Remove "--session token:(some long hash)"
8. Change "--username (username here)" to "--username (desired name)"
9. Run This New Command.
I have attached a batch file that runs the game with this modified command. I was not trying to make a cracked version, I was trying make sure nobody else can. I hope I explained this clear enough. If not, let me know and I will make a video.