I drove by our local Sonic today and the Sonic sign says 50 cents corndogs all day on Halloween.  It also says that kids in costume get a free corndog and drink from 4:00 pm til 8:00 pm on Halloween.  Might be a nice way to have an easy dinner before trick or treating.    

I did a little searching online to see if these deals are bigger than our local restaurant.  It looks like the 50 cents corn dogs deal will be in most Sonic restaurants.  I didn't see anything online about the free kids deal, so it might be a local deal only.  Check with your local Sonic to see.