In a medium bowl, combine cracker crumbs and brown sugar. Stir in melted butter. Press the mixture firmly into bottom and up sides of a 10-inch spring form pan. Bake for 8 minutes and let the crust cool completely before spreading the pie filling over it. You can also cheat and use a pre-made graham cracker crust pie shell from your local grocery store.
In a large bowl, with an electric mixer at medium speed, beat cream until slightly thickened. Gradually add the sugar and condensed milk and mix to combine. Beat in lime juice, lime zest, and half-and-half. Once the mixture as reached desired flavor and consistency, gently spread pie filling over cooled crust. Cover and freeze for 4 to 6 hours or until firm. Cut into wedges and garnish with fresh lime slices, serve cold.