Challenges here are indeed zestful and really delightful.
OK, I may have exaggerated a bit, but hey! You don't even have to rearrange the letters!
By the way, this isn't really my 20,000th post on TPM (many have been lost), but it's the post that makes the little number under my name become 20,000, and since Louis posted a visitor message on my profile to point it out, I might as well let him know I've noticed.
Next challenge: write a sentence of at least 20 words whose only subject is itself.