This tupper-ware case holds everything I need for a weekends worth of fly fishing, not including my waders. Everything for wading is held in an identical plastic box. I only need to grab my rod case. I keep this and my rod case in the back of my mini cooper from the first day of the season till the last. I never know when good weather will hit or the phone will ring. This way I am always ready.
Extra flies and leaders.
Multiple lines cassettes.