Measuring just 114.8 x 76 x 23.8 mm, the ZBOX pico PI430AJ is among the smallest PCs that Zotac offers, yet it comes equipped with two of Frore System's AirJet solid-state active cooling modules. These use membranes vibrating at high frequencies to move air, making them quieter than a traditional fan.https://www.notebookcheck.net/Zotac-launches-world-s-first-mini-PC-with-solid-state-active-cooling.760328.0.html
I hope this tech reaches further brands, because Zotac is famous for being overpriced.
"AirJet" tech looks very promising.