Home FTP server – access from internet

I want to host a small ftp server that i (an others) can access files from over the internet.

Im running XP pro
DSL connection

What would be the cheapest way of doing this?

I do not need to host a lot of files, maybe 4 GB at the most.

I have looked at several 3rd party softwares online. I am not sure if it would be better to just use windows web sharing. I have never set it up before. I figured somebody here has configured something similar in the past. As always free is best!

Thank you!