I can make resources available on the following public ftp servers:
Anonymous ftp server at Sonic.net
This one is fast, always available, and doesn't require passive mode (see below), but it isn't always on: you have to notify me before you can put anything there. Then after I've opened it, log in as “anonymous,” with your e-mail address as password. Upload directory is “incoming.”*
The public directory is open to anyone who knows the user name and password you need to log in. No download quotas, but transfer speeds are limited. Uploads are permitted in the “uploads” directory.*
Although you can do ftp transfers with some web browsers (Mozilla does well), it generally works better to use a real ftp client program (I recommend FTP Explorer or FileZilla).
With many ftp servers, including my home server, it makes a difference whether your ftp client is in “passive mode” or “port mode.” If you pick the wrong one, the client will connect to the server, but it will take a long time to get a directory listing of files. Unfortunately, you don't always know which way will work, so you often have to try connecting both ways. Internet Explorer 6 can do passive mode, but it's a pain in the ass: you have to choose Tools : Internet Options from the menu, and on the Advanced tab, check the “Use Passive FTP” box (under “Browsing”).
On my servers, you can see the upload directories, but you can't open them or see what's in them. To upload a file, just drag the file and drop it on the uploads folder. You won't see the file after it's transferred, but your ftp client should tell you that the upload was successful. I'll likely see it within a day, but feel free to send me an e-mail and let me know it's there.