For example, Don Rickles--yes, Don Rickles--made a cover-featured guest appearance in Jimmy Olsen #141. Click the link to see why Kirby+ Rickles = madness!!
Anyway, DC went so far as to give comedians their own comic books. Whole titles!! Bob Hope had a comic book at DC--The Adventures of Bob Hope lasted 109 issues!!
And then there was Jerry Lewis. The Adventures of Dean Martin and Jerry Lewis ran for 40 issues in the 1950's, and after the comedy team broke up, The Adventures of Jerry Lewis sprang forth instantly to replace it, and ran until 1971!!! The title produced such amazing crossovers as this:
Now, not to say that this particular comic was good (the few issues that I actually read were abysmal), or that we need Jerry Lewis back in the DC Universe (but why not?).
But since DC feels the need to constantly reinvent itself, why not revive the comedians-in-comics concept? Instead of Jerry Lewis, what about Jeer Seinfeld? Steve Martin? The Adventures of Carrot Top? I know I would read a comic book featuring George Carlin or Gilbert Gottfried.
Just picture the new DC Universe, teaming with panels like this: the Joker, in a kangaroo suit (don't ask), pointing a machine gun at Jerry Lewis. Translate that to a Parallax-possessed Kyle Rayner pointing a meson gun at Rita Rudner, and we have a certifiable hit on our hands.
And at least it's better than that Countdown crap.
Cover and panel from Jerry Lewis #97, 1966