From Jeff Phillips:
Libcurl.NET exposes the open-source cURL library to C# and VB.NET clients. Supported protocols include FTP, FTPS, HTTP, HTTPS, File, Gopher, Telnet, DICT, and LDAP. Developers may particularly want to check out Libcurl.NET's support for FTP, since that protocol isn't expected to be included in Microsoft's standard system.NET classes until .NET 2.0 is released. The product may also have interest for developers who have worked with cURL and/or Libcurl under Unix or Linux. The product includes MSDN-formatted API documentation and a number of sample applications in C# and VB.NET. Version 1.3 is completely open source and has been updated to work with the latest version of Libcurl, 7.13. It is now distributed as a ZIP file.