Planar's Writable 4K UltraHD Display
Planar is the company that bought out Runco a few years back, but if they are still making projectors they weren't showing them this year. The passing of Runco as a distinct entity is notable in the annals of CEDIA EXPO. That company nearly always had one of the largest booths at the show.
ADDENDA: In scoping out the Wisdom Audio demo (discussed elsewhere here) I noted that it was using a 3-chip Runco DLP projector. Under Planar, Runco projectors are indeed still available.