I've yet to get around to it but still intend to mess with producing a pseudo fig-8 response from two miniature omnis, as discussed in another TS thread a few months back. Will post about it whenever I do. Although cardioids are likely to work better, it would be very cool if I could produce a M/S recording using just two close-spaced miniature omni channels. Recording them to separate channels would allow for close matching and combining in post as discussed earlier in this thread: First closely matching level, frequency and phase response, then summing the two to produce Mid, and differentially summing them to produce Side. Imagining running two such pairs in a hat, in place of a traditional head-mounted pseudo-HTRF omni pair, into a four channel recorder. If it doesn't work out I just end up with a typical head-baffled omni pair, except now with full redundancy up to the recorder. If it does I gain the ability to dial in some front/back directionality if desired.. and/or derive separate front/rear facing pairs perhaps. Yeah, something of a reach. But if wishful thinking or just for fun (bit of both really) such a setup wouldn't compromise the straight two-omni recording.
What really brought me back to this thread was to share this, sort of circling back to the start..
[snip..] I was thinking about passing trains or something. [snip]

Figured you might enjoy this recording of a rather charismatic passing freight train made on my way home after a concert last one balmy summer night in 2007.
https://drive.google.com/file/d/1d3Rpx2rlcBLfI9w9J-dd8J-TxC4cD6f5/view?usp=sharingLate night freight & car 2007-04-27.flac
Length_06:28, 62.3MB
Features crossing gates, passing train, muscle car driving off into the night.
DPA4060>CA-UGLY>Edirol_R09