I rent two virtual private servers, of which one is in the UK, and the other is in the USA. Recently I concluded that I was paying too much for my UK VPS, so I switched providers, which meant a change of location from London to Manchester, along with a change of IP address. During the migration, I decided that I didn't particularly like the authoritative DNS server I was running (PowerDNS), and so I decided to write my own authoritative DNS server. This caused the migration process to be rather longer than I expected; it changed from a few hours to about a week, but the end result was much more knowledge of the DNS protocol, a new side project, and a DNS sever which I'm happy with. Also, in the past few hours, my USA VPS migrated from Atlanta to Dallas due to my hosting provider wanting to phase out their presence in Atlanta, and this migration also carried with it a change of IP address. This migration was fairly quick and painless due to most of it being an automated process on the part of my hosting provider. The fact that the migration was quick was also helped by the fact that the VPS was already running my self written DNS server, and thus didn't prompt me into a new project.

Perhaps at some point in the future I'll finish extending this DNS server code, and actually publish it.