This is the Swiss File Knife (SFK), a command-line multi-function tool
created by StahlWorks Technologies.

SFK was made to make things easy.  File exchange between machines, find
duplicates, find and replace text, list directory tree sizes, and tons
of other functions for daily tasks -- all contained within a single,
truly portable executable.

Forget about installing dozens of tools on every new machine, battling
with missing or wrong versioned DLL's, missing admin rights, missing
package dependencies, user account configurations, spammed registries
and endless time wasting in general.