I found a 3 inch long tomato hornworm last week on my tomato plant COVERED with the eggs of that parasitic wasp that eats them...so I left it there...to be consumed.
Ironically, I know this because about three weeks ago I found an ACTUAL Luna moth caterpillar (or possibly Polyphemus, it's hard to tell the caterpillars apart) crawling along the sidewalk in Flushing and brought it home to raise and release (it's currently pupated and resting).