Batman: The Animated Series Easter Egg - Bam! Adam West, et al!

There are a few gems in this one: First of all, the Gray Ghost character is a reference to Batman creater Bob Kane's inspiration, the Shadow (with the hat and the cape). Secondly, the voice for this character is Adam West, who played Batman on the 1960's show (cool). Thirdly, the villain, the Toy collector, looks like, and is voiced by top BTAS designer Bruce Timm (all right). Fourth
, the "Gray Ghost" posters in Bruce's personal collection looks just like the Batman posters for this show (also seen on the end credits). Finally, in the final shot of the show, a 'People' magazine can be seen with an article about the Gray Ghost. In the corner is a picture of Matt Haygen, aka Clayface, a former actor who probably would be featured in Gotham's People Magazine. Pretty sweet, huh?