I love being able to go through Tezuka's older works now and catching some of the references. He didn't really throw that much into any one specific strip (maybe an occasional sketch of R2D2 or the Enterprise on a poster in the background), but when he did put stuff in, he went full-out. One example is in "Don Dracula", when Chocola is crying for help after her friend from the science fiction club throws himself into a river (even though she's strong for her size, she can't rescue him herself because vampires are weakened by water). She hopes that Astroboy, Superman, Kamen Rider or Ultraman will save him (they don't, because in this universe, superheroes are fictional; only creatures like vampires, werewolves and swamp men are real).
Earlier in the same chapter, a flier advertising plastic models for sale shows pictures of Superman and Darth Vader .
But, way, way beyond that are the shout-outs to his friends in the industry. The best one was in one of the episodes of "The Crater", where three alien invaders suck Tezuka's brain to get information about Earth. The "military intelligence" they send back to the main army consists of the names of the regular contributors to Weekly Shonen Champion, many of whom were Tezuka's friends or previous assistants.
Well, here we get another shout-out, only this time it's a list of some of the most popular anime and live-action shows on TV, and most of which either came from his own studio or from the studios of his friends or competition. I don't think these kinds of shout-outs occur in his longer works, like "The Phoenix", "Black Jack" or "Astro Boy", but he published 700+ volumes of work, so I doubt I'll ever know everything he's done.
What kind of TV do you watch?
教えてやろうか！キャプテンフューチャー 未年少年コナン ルパン三世 ガッチャマン ゼンダマン ザンボット グンダム ヤマト
I'll tell you! Captain Future, Future Boy Conan, Lupin III, Gatchaman, Zenderman, Zambot, Gundam, Yamato.
ハーロック 仮面ライダー ウルトラマン ウルトラセブン ウルトラマンエース 帰ってきたウルトラマン ウルトラマンタロウ 太陽にほえろ 七人の刑事 かっこよくて強いのが好きさ
Harlock, Masked Rider, Ultraman, Ultra Seven, Ultraman Ace, The Return of Ultraman, Ultraman Tarou, Taiyo ni Hoeru (Barking at the Sun), Detective 7 - I love strong characters.
I want to mention here that "kakko yokute tsuyoi no ga suki" is a little touchy when translated into English. Literally, it's "figure good . strong . like", or "I like cool, strong guys / men". This could be taken the wrong way. That's why I changed the wording a little to "I love strong characters". It retains the same meaning but loses the sexual innuendo.