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- Cube (1997) cost 350k.
- Beyond the Black Rainbow cost a measly 1 million and it's more of a cult/niche flim, but it looks like it cost way more, they did a lot with just atmosphere and practical effects.
- Coherence (2013) cost just 50k and I found it gripping.
- And of course The Man from Earth (200k), if you watch those back to back you wonder why this one even cost that much.