There are thousands of wasps which often look simlar, it's unwise to kill them as they do have a purpose. Some take flies for their young, some take bugs according to the species, and some parasitize bugs.
What you have appears to be Campsomeris plumipes.
http://bugguide.net/node/view/...
http://www.americaninsects.net...
These wasps are parasitoids of soil-inhabiting scarab beetle larvae
http://entnemdept.ufl.edu/crea...
Notice the legs, they are not like a cicada killer's, the eyes are also different. These are very unlikely to sting you.
The form in Florida, Campsomeris plumipes fossulana
https://www.google.co.uk/searc...
