do airlines in any other countries try to have significant registrations?
Aer Lingus block-booked EI-FK_ for their F50s in a clever play both on the manufacturer name and also in mirroring the original EI-AK_ sequence of their F27s. Someone had fun with that one, though I'm not sure they thought-through the pronunciation of 'FKA.
Then there were the US airlines that like to register N___AA/US/AS etc but that scheme was prone to interruption since you can reserve a reg with the FAA for $10 regardless of whether you have an aircraft. Always worth taking a punt to register N777UA and seeing if you can flip it on to an interested airline
