Local newspapers (notoriously unreliable) suggest that there WILL BE AN OPEN DAY AT DON MUANG January 14, 2012 "near the Cargo Area" , I assume this is the usual location at the south western side. Opening time: 08.00-15.00. No further info available. Go at your own risk.
This information is from early May 2011. As mentioned by a previous poster, you can spot LANDSIDE in Terminal 3. For pictures it is next to useless as you get weird distortions due to the double glass. Unfortunately you have to make a choice of standing at the right facing North where you can only s...