At the subway station near my apartment, there's a door with the word "SIGNALS" written on it. I see that door pretty much every day, and so at one point during the academic year, it occurred to me that the following is a palindrome:
SLANG IS SIGNALS
The nice thing about this palindrome is that it's reasonably meaningful. "Slang can function as a linguistic cue that you belong to the same in-group as someone", or something along those lines.
After discovering this palindrome, I decided to Google it, since I was sure other people must have independently discovered it in the past. Sure enough, some people had, but there seemed to be surprisingly few.
One member of that small list is someone by the name of Dean Blehert, who has a long list of palindromes titled Light Verse.