2. The Rainbow Batman
No one could blame you for being cynical about this image. At this point, we've been trained to look at old covers like this and instinctively assume that it has nothing to do with the actual comic book inside, like the time it appeared as though a woman would have agency in her own story while wearing clothes on top of her sports bra and hot pants. With Detective Comics #241, what you see is what you get (besides that "red" costume being more of a fuchsia, or magenta at best). In the issue, Batman really does change costumes several times in a matter of days, leading up to this:
All to crack down on some camera-stealing goons. Batman reveals that his plan all along was to draw attention to himself and away from Robin, whose alter ego Dick Grayson had hurt his arm earlier. Robin was the only one who could finger the crooks, and Batman was worried about the infinitesimal chance that someone would link his sidekick's injury to Grayson. Following the only rational course of action, Batman dipped spare batsuits in increasingly fabulous flavors of Kool-Aid and drove around in a parade. After that, he's got one more task ahead of him: washing out all that Mountainberry Punch.
1. Bat-Baby. Just...Bat-Baby
Eerie rays of light were pretty common in the era that Batman #147 was published. All it took was a disgruntled kid from the A/V club and a modified slide projector and - BOOM! - instant transmogrifier. After 20 years on the job, Batman should have known better than to just stand there and get zapped into a small child, but that's the predicament he found himself in. Instead of constructing his own age ray or faking sick to stay home and play Final Fantasy, Batman pledges to use his newly stubby body to enact some misplaced kind of poetic justice.
To review: Batman was turned into a kid, is mocked with the moniker "Bat-Baby" by some thugs, and then proceeds to put on a Sunday school outfit in an apparent agreement about his status as a baby. Whatever the twisted logic, it obviously works, as bad guys across the city are fucking terrified by a toddler in short overalls with full man-strength. Their gargled screams of "BAT-BABY!" are without any shred of irony. In the end, Batman is returned to normal size but we are deprived of a pivotal scene in which Bruce Wayne grows out of his clothes and is left completely naked in front of people who wanted to turn him into a 4-year-old.
I guess some things are best left to the reader's imagination.