The Cobrahead line of garden tools are the most useful and accessible tools I have every used for purposes other than gardening——and top notch for all gardening purposes, too. Based in Cambridge, Wisconsin, and founded in 2002 by Judy and Noel Valdés, Cobrahead is a family-owned and family-operated business that produces a multi-purpose hand tool and a stand-up hoe, both with a sharp long "steel fingernail". Essentially, the Cobraheads are indispensable multi-purpose tools, with ergonomic handles, useful to cultivate, dig, plow and rip, create furrow lines or transplant roots. The sharp blade and sturdy construction allow precision and accuracy in whatever job inspires you.
Invented out of necessity by Noel Valdés, "The initial idea for the CobraHead Weeder and Cultivator came to be when I was working with the old tool and a tine loosened and fell off. Scratching the dirt with the single tine, I decided that the digging and cutting ability of the blade might make it a handy weeder. I mounted the blade into a short handle sized piece of wood and began grubbing around the garden bed. It became readily apparent that the tool worked very well as a weeder and also did a reasonably good job of cultivating and digging small plants for transplanting."
I especially love using it to weed and tear up the roots of grass that form under the small brick porch at my home in the southwest desert. The intricacy of control that the handle allows for also works well for cleaning random accumulated blades of grass from cactus gardens. The clean clear cut of the Cobrahead blade is quite satisfying. If you are not entirely happy, Cobrahead will "give you one year from the time of purchase to make up your mind. If you don't find the CobraHead to be a useful and well made tool, return it and we will refund your purchase costs including original shipping costs (USA and Canada, only)."
While Noel has been called "Mr. Cobrahead," it is "Judy Valdes [that] wears the most hats. She fulfills positions that include chief financial officer, traffic manager, customer service representative, packaging specialist, and primary family chef. She forces the rest of the team to think practically."
Here are some videos from Cobrahead to give you an idea of possible uses – if you don't already have some in mind.