You got ch0wned, my friend. The command should have been "sudo chown ..." and after you accidentally pressed enter, you should have said, "Oops" and not entered the password.
Well, lesson learned. Now, what to do?
Get your latest backup and dump all the files and their ownerships. Then go through them group by group and repair the ownerships. Do not reboot until you finish fixing it or you may make it much harder to repair. (You can even turn the dump into a script if you wish.)
If your system is too hosed for commands to work, you'll have to boot from a rescue CD or USB disk, mount the system, and repair things like
/bin to get the system usable.
It's going to be very painful. Sorry.
Alternatively, backup the current state, restore from a working backup, and then manually restore from the backup you just made any files that aren't current in your backup.
See this answer for some tips on recovering installed system files.