Install it using pip:
pip install offer

You can use it from the CLI:

offer ~/path/file.ext

It'll try to host the file on port 80 by default and will fall back on port 8000 silently if it is not run with the correct permissions. You can provide a custom port via the --port argument. Then from another computer/tablet/phone, you can either point the browser at the IP address printed out or use curl.

Note about cURL

Remember to use the -L flag with cURL to follow redirects.