These three pictures are screen captures from a music video by a group called The Sursiks. The song is Little Paper Airplanes. See it here.
I'm not going to explain how little paper airplanes or the Federal Reserve and the money supply relate to these pictures. You can watch the video too.
Yes, these pictures have been photoshopped by someone. They're still funny.
Found via WFMU Beware the Blog.
Other pictures of tubas - well, Sousaphones actually - appear in this Mixed Meters post. A picture of a Wagner tuba (like the one held between the legs of the strong man in the last picture) which has been made into a lamp is here. (Scroll down.)