The vanity doesn't have to have 0 in it, it can be one of the other numbers for other parts of the country. Local gal just upgraded to extra and changed her callsign to K2***. Depending on your license, you can shorten it to a 1x3, the x denoting the region number. I saw a guy with a ham license plate and a (had to be vanity) callsign of N0MUD. I think a lot of the Extras get theirs shortened for DX work, as the less letters to read out, the easier it is. I looked into a vanity for myself, dropping one letter, the D off my callsign, and was hoping to ditch the K in it for an N. The last three letters of mine happen to be a gamer's phrase, that a few swore I had to have chosen a vanity to get,lol. Alas, when I looked up callsigns, somebody in MN has the exact callsign I wanted, so I may have to be content with just dropping my D.
Wife and I stopped at the candy store Saturday, and I picked up the study guide for the Extra test. That is going to take some studying.