There was a period, in the late '60's and early '70's, when it became acceptable, and nearly even common, for DC heroes to break the Fourth Wall on their covers. Take, for example, Flash #222:
It seems incredibly cheesy by today's standards, doesn't it? It's hard to imagine one of today's DC comics doing this (unless it was Grant Morrison doing a pastiche...).
Still, it does make a sort of sense. Since comics readership skewed younger in those days, it made sense to try and draw in readers by making them feel involved. And you've got to admit, it is a catchy and involving cover.
DC even went so far as to say that "our" world was part of their multiverse. The "real" world, where super-heroes were only comic book characters, was "Earth-Prime," an actual DC universe just like Earth-2 or Earth-S. DC characters in this period popped up on Earth-Prime, and Earth-Prime charatcers, especially comic book writers, turned up on Earth-1, usually in comics written by Cary Bates. And lo and behold, this issue of Flash is indeed written by Mr. Bates. What a surprise! With such crossovers going on, it's not completely insane to think that we poor Earth-Prime inhabitants could help out our heroes...just like the audience bringing Tinkerbell back to life by clapping!!
OK, it is completely insane. But that's all right, because the "help me, readers" scenes portrayed on the covers invariably NEVER appeared on the inside. Nothing even close. Just good old late Silver Age/early Bronze age DC bait and switch.
If my collection were more organized, or if I were as industrious as Mark, I'd run you a whole series of these covers, with DC heroes begging for help from their readers. Because I love them to death! But I'm lazy, so i'll just have to hold out hope that DC comes to their senses and starts having their heroes break the Fourth Wall again.
SPOILER ALERT: Flash doesn't kill us all. It's all a plot by Sinestro. And of course, the cover is a lie, because Green Lantern doesn't ask for help, he doesn't need extra willpower, and he never zaps an attacking Flash. That's another good point about these covers: they were usually far, far better than the stories they were pimping for.
Readers, help me!! I need all your willpower to help me prepare for my 100th post, coming soon!! Focus all your thoughts on me!!