Free .NET FTP component gives .NET developers:

• C# FTP functionality
• VB .NET FTP functionality
• Robust and proven FTP .NET library
• C# source-code included
• free for commercial use (LGPL)
• Downloaded over 200,000 times!

Non-GPL source licenses can be also be purchased.

edtFTPnet/Compact is a port of edtFTPnet to the .NET Compact Framework, versions 1.0 and upwards. From $199.

edtFTPnet/Express adds directory transfers, SOCKS proxy support and a powerful collection of FTP GUI components from $149.

edtFTPnet/PRO adds secure FTP capabilities with support for SFTP (FTP over SSH) and FTPS (FTP over SSL), from $399.