Because I'm an absolute nerd, I wanted to get a vanity call sign-basically change my call sign from the randomly generated call sign from the FCC to one of my own choosing. The process isn't just "Here's what I want, now give it to me"; I had to provide a list of 25 call signs I would like, and the FCC would review each one to make sure it wasn't already in use. They also had to verify I had to violations on my license and I was current on any outstanding fees.
After 3 weeks, I finally got the call sign N5TDS, with 5 being the region I'm in (Texas) and TDS standing for Texas Dark Skies.