Sometimes you're supposed to top a casserole with toasted bread crumbs, and you don't have any bread to toast and then to um, crumb..le? Anyhow a list of alternative crunchy toppings.
*panko breadcrumbs
*crumbled saltines
*crumbled ritz
*corn flakes
*cornbread crumbles
*smashed croutons
Or, you know, always keep some bread in the freezer!