4 Uses of Dry Ice
Most often I use Dry ice to seal up plastic buckets with bulk food, but there are a lot more dry ice uses a guy can do.
You can also use dry ice to force carbonate beverages, but if you do this it can cause the bottle to explode so be careful.
I have also used it to make fog (which is not a prepper use I guess)
Something else I find to be a fun on of the dry ice uses is if you put cubes of dry ice into a container of rubbing alcohol the CO2 will super chill the alcohol making an extremely cold liquid that replicates some of what liquid nitrogen can do.