Collections that provide Unix tool ports to Windows users:
- Cygwin (Entry).
- UnxUtils (Entry).
- Gow (Gnu On Windows) (Entry).
- Busybox (Entry). One executable but tools are usually more limited that their full versions
- uutils. Cross-platform (including Windows) ports of Unix tools, like coreutils in Rust.
- MSYS2 (Entry).
- GnuWin (Entry).
- ezwinports (Entry).
- see here for more.
- Moluccas (TumaGonx Zakkum) (also wget and aria and CDRTools)
- eternallybored.org (Jernej Simončič) (wget, netcat, gifsicle)
- MobaXterm (Entry). GUI application focusing on networking with many Unix CLI tools.
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Multiple tools form one developer/group (if you liked a tool, you may like its sisters

- Built-in Windows tools
- Sysinternals
- BYTE* Tools
- cmdtools.com (Archive Link)
- Core Technologies. A couple of the free tools are CLI.
- DSToolBox
- F2KO CMD Tools (Archive Link)
- Gammadyne's Free DOS Utilities
- Helge Klein
- Horst Schaeffer's console tools
- Jason Hood
- Joakim Schicht
- LTRData (author of ImDisk)
- Luigi Auriemma
- p-nand-q.com
- pc-tools.net
- Rob van der Woude's Scripting Pages (Some of the tools are others', some are his)
- Softspecialists
- Stefan's Tools. A couple of the free tools are CLI.
- Uwe Sieber's Homepage
- West Mesa Tech
- xs4all
- Yori (many tools with Yori itself that perform various functions).
https://ccrma.stanford.edu/~craig/utility/
Some specialized tool groups:
CompressMe.net (Ilya Muravyov) (Compression Software. See Encode's Forum for more)
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A single tool with many functions:
- Swiss File Knife (forum topic)
- Busybox. See under Unix Tools.
- uutils. See under Unix Tools. Currently available: Coreutils
- NirCmd (forum topic)