Batman: The Brave and the Bold is a newer cartoon, but the strength and virility of the innuendo is staggering. In a lighthearted episode, the Birds of Prey (Catwoman, Huntress and Black Canary) find themselves on stage in front of a bunch of goons, and proceed to improvise a song to entertain the unruly crowd.
They end up belting a ballad that all but explicitly judges the male male members of the Justice League on their sexual prowess. They croon about Green Lantern's "little thing" being "pretty strong." If you don't think that they're talking about a cock ring, just wait til you see what they say about the Flash.
That's pretty embarrassing, but as usual, Aquaman gets the rawest deal.
Of course, all pretense goes out the window when it comes to singing about Batman.
This might be a good time to mention that this was actually a "bonus episode" that was featured on the DVD collection. But judging from the watermark from the video, this aired in syndication at some point, so somewhere there's a little kid who doesn't realized they just heard a song about Catwoman banging Batman.
This last one is especially disturbing considering that a) In many continuities, Huntress is the daughter of Catwoman and Batman and b) It sort of implies that she wants to see Batman's butthole? Then again, you gotta admit you're curious -- after all, Batman is prepared for any situation.