Well whether you call it small, tiny or microscopic depends only your perception of how small is small enough!!
This amazing machine is based on Linux operating system and unbelievably measures hardly 35mm×19mm×19mm!!
• 32-bit ARM 7 Netsilicon NS7520 processor (55MHz)
• 2MB flash storage
• 8 MB SDRAM
• uClinux 2.4.27 Big Endian operating system
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picotux - smallest Linux computer in the World