Exploding pulse jet in a bottle.
Linked from Instructables.com project.
This is a meths fuelled Reynst pot running to destruction. The 'puttering' noise is hot gasses being forced out of the top hole as the flame contracts and expands. This type of device does not provide much thrust but is extremely efficient as a heating device.
Make one yourself - I used a Tesco's olive jar with a 10.5mm hole in the lid. Experiment!
