Try AquilaOS

The i386 base system, running in your browser on v86, a PC emulator. It runs from memory: nothing is kept, and nothing is sent anywhere.

About 5 MB to download. Log in as root, with no password.

Things to try

uname -a: the kernel's version, and the compiler that built it
ps: the processes, with the kernel's threads in brackets
cat /proc/interrupts: interrupts, by IRQ
ls /sbin: aqbox's system tools, and runit
sleep 100 &, then jobs, fg and Ctrl+Z: job control

What's in it

The live system is AquilaOS's base system for i386 on a 2 MiB disk: the kernel, newlib, dash, sbase's utilities, aqbox and runit. Its root filesystem is in memory, so whatever you change is gone when you reload the page.

The ports aren't included, to keep the download small: there's no bash, X or Doom here. There's no network either, since v86 doesn't emulate the Intel e1000 that AquilaOS drives. To try those, build AquilaOS and run it in QEMU.

Credits

v86 by Fabian Hemmer and its contributors (BSD 2-Clause), and xterm.js by its authors (MIT). The emulated PC's BIOS is SeaBIOS (LGPL 3.0), as v86 builds it: see its configuration and build script.