Siem Reap Airport terminal
Unlike Luang Prabang Siem Reap has done everything up for tourists in the last 10 years, including the airport. Very modern on the inside and effecient processing of passports/visas - there were about 10 different officials seated around a cresent shaped reception table. You handed your passport and money to the first person and they would check, stamp or doodle something as part of their process and slide the document to their left for the next person to complete their task - this was done 10 times and at the end you collected your passport with a shinny new visa.