Like Unix tee, ntee is yet another Windows command line tee utility that echos standard input back to standard output and then redirects it to one or more files.
To echo and redirect the output of the dir command to a new file:
dir | ntee log.txt
By default, ntee will overwrite existing files. To append instead:
dir | ntee /a log.txt
And for multiple files:
dir | ntee /a log1.txt log2.txt
Enjoy!