Birds
Two with der (Storch, Papagei), two with die (Krähe, Schwalbe).
Personal care
Two with das (Shampoo, Deo), two with die (Zahnpasta, Creme).
Science
Das Labor, das Experiment, die Forschung (-ung: always die) and die Theorie (-ie: mostly die).
Things with a handle
You hold them by the handle: der Koffer, das Bügeleisen, die Schublade, die Säge.