photo from Editor B, Flickr
I wasn't fast enough to get my own photo but I saw one of these yesterday in a flower container in the yard. I thought it was an earthworm until I saw its head. I went inside and googled it and found out it is a hammerhead worm, a type of planerian. It doesn't eat plants but one variety does eat earthworms and is capable of decimating an earthworm population. The one I saw was about 4 inches long but they can grow up to 10 inches. Thought to originate in Malaysia they are now spreading around the world, probably in imported potted plants. If you see one don't kill it by chopping it up; every piece will turn into another worm. Here's more information on Dave's Garden; you can see in the forum that 2009 is the first year they are reported in Alabama.
And here's one of the few plants that is happy in my yard - an evergreen wisteria I planted last year. It's not really evergreen in this zone but it did come back. This wisteria is not invasive at all and easily contained.