Wonder Twins Zan and Jayna have made a few appearances since the cancellation of the Super Friends TV show and comic book in the early '80s. Robert Washington III and Tom Morgan added them to Captain Atom's Justice League in Extreme Justice, they showed up on Smallville, and most recently they popped in to audition as Beast Boy's replacement on Teen Titans Go!.
If Bobby Timony (The Night Owls) had had his way, they would've also appeared in a short story he pitched to DC Comic. He doesn't say exactly what it was for and why it didn't get picked up, but he recently shared the story on his blog, with the first four pages colored by Jordie Bellaire. Check out part of "Wonder Twins" below, and visit Timony's blog for the rest.