RotaVac is an experimental "centrifugal compressor", designed to be printable as a single piece and spun in a drill or machine to generate a negative pressure gradient.
RotaVac is designed to fit a standard 608 bearing like the sort used in Makerbots, so that a small nozzle (printed separately?) can be fitted through the bearing interior.
This is a pure experiment, and I'll post more when I have a chance to test it!
1.) Print with plenty of infill to make airtight. Print from SD recommended - Plenty of curves in this piece!
2.) Poke Bearing in the bottom
3.) Poke some kind of nozzle through the bearing
4.) Spin it counterclockwise (D'oh!) on a drill and use the negative pressure to create a negative-pressure container.
5.) Aspirate stuff into the container.
Aspirating stuff directly into RotaVac (assuming it works at all) is not recommended, as it'll just fling it everywhere and make a big mess.