I have personally never worked one, but when I was travel nursing they told us about certain states that offer immediate licensure as an RN if you have all your paperwork when you arrive. I will copy and paste some info here from a website I found regarding this:
"Provided all paperwork is in order--and an applicant has a current, active license and no encumbrances--a temporary license can be acquired by walk through or in as little as one day in California, Colorado, Delaware, Idaho, Kansas, Maine, Maryland, Missouri, Nebraska, North Carolina, South Carolina, South Dakota, and Vermont. Depending on each of these state's individual policies, fees vary and temporary licensure may be valid for as little as eight weeks or as long as six months. Keep in mind, too, that there may be additional requirements to meet. For instance, a nurse must make an appointment with the Board of Nursing in North Carolina to obtain a temporary license, even though it's recognized as a "walk through" state.
Other states give nurses similar opportunities. Those who are interested in practicing in the Last Frontier, for example, can contact the Alaska Board of Nursing to schedule an appointment for a walk through. And while temporary licensure is not issued in Virginia, RNs who wish to practice there are able to work under any current license for up to 30 days, the maximum length of time to process a permanent license in the Old Dominion State. "
Hope this helps!!