I shall review some key features of the three ten-dimensional string models with broken supersymmetry that are free of tachyonic modes. Their leading back-reactions are runaway “tadpole potentials”, which have important effects on their ambient spacetimes. When these are explored in detail within the low-energy effective theory, some surprising features emerge: ·Tadpole potentials can drive interesting spontaneous compactifications; ·In Cosmology, they can lead to the peculiar “climbing scenario” for fast-to-slow-roll transitions. Puzzling instabilities typically accompany broken supersymmetry in String Theory. However, they are absent in the former setting, and point to a mere breakdown of isotropy in the latter, which resonates with the very emergence of compact dimensions. I shall address these issues, trying to emphasize potential lessons and some key open questions.