<< There ARE legitimate uses for FTP, you know. >>
<< Yea, but very few. >>
You're joking, right? Or else your perspective is very narrow. Or you are stupid (I'm sure you're not, I'm just covering all the bases)
Practically every software company has an ftp server. Most engineering firms I've worked with have ftp servers. Lots of graphics design shops have ftp.
But more to the point of the original poster's question, I and several of my co-workers have ftp servers at home so that we can exchange work-related files with our home PCs. I know it's hard to believe, but some people actually have DATA files because they do actual WORK. No pirated stuff at all. And quite secure using SSH and sftp.
zmzhang - please make sure you have your security down tight, as ftp is notoriously insecure. I would suggest using SSH to secure the connection, and also have all your file and directory permissions and user accounts properly configured. I would not run an ftp server from Windows 95, 98, or Me, BTW - unless you want your data destroyed by hackers within a day of setting it up.