The DSP library for Taros, aptly named TarsosDSP, now includes an example demonstrating the flanging audio effect. Flanging, essentialy mixing the signal with a varying delay of itself, produces an interesting interference pattern.
The flanging example works on wav-files or on input from microphone. Try it yourself, download
Flanging.jar, the executable jar file. Below you can check what flanging sounds like with various parameters.
The source code of the Java implementation can be found on the TarsosDSP github page.