The titular "post" in this case leaning toward "the station or rounds of a person on duty." This was my table in this year's GenCon art show. (Shooting at f/2 with the available light made for quite a shallow depth of field. Sorry about that. Next time I'll try a flash.)
This year I wanted to emphasize my paintings -- which were mostly new -- and my playmats. The playmats would easily take all the table space I could get, but I also wanted to have paintings on the table, where people could get a close look at them. While sketching some display ideas it struck me I could use an LCD desk mount. (I also considered extending the tabletop for more display surface, but let that idea go for another time.)
I think they worked admirably. The paintings were convenient for passers-by to see, were secure, and didn't interfere with looking through the piles of mats on the table.
The LCD arms I used are model 5402 from MonoPrice.com
I've also been asked about my panel extenders. They, along with the stiffeners and support bar, are from ProPanels.com. The GenCon panels are 38.5" wide, with dark grey carpet, if you're looking to match.