While watching Hulu a couple weeks ago, I heard a really interesting mashup during an Intel commercial. The commercial incorporated Intel's four-note sonic logo into the (arguable most well-known piece of classical music ever?) first movement of Beethoven's fifth symphony.
Regardless of how you feel about Intel using this great symphonic work to sell products, this is the type of thing that becomes possible once pieces of music are no longer protected by copyright and enter the public domain. Intel couldn't have made this kind of commercial, for example, by remixing a recording of "Born in the USA." (At least, not without the lengthy and usuall expensive process of clearing it with Bruce Springsteen's record label.)
Musically, the first thing that sticks out about this mashup is that Intel has changed the key of Beethoven's symphony. This movement is famously in C minor, but in the commercial, it's in C-sharp. Knowing nothing about the production of this commercial, I have only a guess about why this decision was made. It seems possible that the recording of the symphony that they used to make the mashup needed to be sped up a bit, and instead of keeping the pitch constant as the tempo was adjusted, the mashup artist went ahead and kept the pitch shift as well. Here are the two motives:
Beethoven
Intel
The way that these two motives are integrated together in the mashup, I think, illustrates the way that the symphonic motive (with the way that it completely permeates the entire movement) acts as a sort of sonic logo in much the same way that the Intel motive does. Both are designed to stick in our heads. For Intel, we are meant to remember the logo while we're shopping for computers; for Beethoven, we are meant to remember it in order to perceive the organic structure of the work.