No matter what sci-fi setting you are using, if the PCs are around starships at some stage they're probably going to ask what's in a particular cargo container. 101 Starship Cargos offers a quick list for the busy gamemaster of possible contents - some mundane, and some surprising. Several examples include:
12. Bolts of cloth
66. Money (counterfeit)
96. Stun batons
The next time your players want to stick their head in a random cargo container, you won't be caught out!