Battaglia chord
The battaglia chord is an essentially tempered dyadic chord of marvel temperament, the marvel (225/224) tempered version of
It was considered by Mike Battaglia, who regards it as "trippy". Although the octave-reduced voicing for this chord is 1-5/4-7/5-3/2-7/4-15/8, a simpler and less compact voicing is 1-3/2-5/2-7/2-15/4-45/8, or 8:12:20:28:30:45. Other less compact voicings are also likely to be preferred, for instance 1-5/4-7/5-7/4-3-15/4, etc.
An example of a musical fragment built around this chord can be found at the end of this example: http://soundcloud.com/mikebattagliaexperiments/happy-birthday
This chord is noteworthy for existing in 12edo, although its intonation can much be improved in a tuning such as 22edo, 31edo, or 53edo.