Must Have Boondocking Items?

Thanks to everyone for all of the great info! Sadly I have nothing to share of my own yet but I will after the summer of 2016. I plan to take my 2 teenagers on a cross country trip (from PA, to the west coast, and back) over about a 6 week time span. (Our gear includes a tent! :) )We will be working with a shoe-string budget and boondocking seems likt the best option for us (considering both our budget and our love of the great outdoors.) All of the tips here (I read all 17 pages!) have been compiled into a packing list, tips and resourses documents. I'll keep checking back so would love to hear if anyone has any other info they think would be important. One question I do have, what are the gun laws in other states? I was already thinking about carrying a small hand gun just for safety but was unsure of the laws of carrying it across state line.