104
ICANN is Accepting Suggestions for new TLDs (for $227k) - what would you pick?
(www.theregister.com)
This is a most excellent place for technology news and articles.
All two letter TLDs are exclusive to countries. So unless you make a country called Ergostan and Dbaseistan and get them internationally recognised you are out of luck. However, if you manage you don't have to pay the fee!
.er is already the country code for Eritrea
Damn, if colonies were still a thing, Italy would be the empire of domain hacks, with .it, .er and .so
Edit: before you think I'm pro-colonization, my post was just a historically accurate joke