I remember we had a thread like this on the Wii board, but I've seen the DS on TV some and thought we should have a similar topic here.
Basically, if you see product placement of the DS on a TV show, mention it here.
It's quite common to see Dr. House playing a DS (even GBASP or PSP on occasion) on the FOX show House MD.
And, today, I was watching a TiVo'd episode of King of Queens and Doug was playing an... odd version of Nintendogs on his DS. He said he was "training his virutal puppy" and wacked it with a newspaper.