Hey, digg.com, yes, you! Your webserver just sucks. Have you ever found the time to read the relevant HTTP-related RFCs, like 1945 or 2616? I don't think so, otherwise you'd know that the User-Agent request header is not mandatory. Recommended, but definitely not mandatory. So why in hell's name does your webserver simply close the connection when sending an HTTP request without User-Agent header, and why does it keep the connection open without any response when I send a request without User-Agent header but with a Connection: keep-alive header? I've never seen an HTTP server implementation that is broken in a more braindead way. If you don't like clients w/o User-Agent header, why couldn't you at least reply with a nice "HTTP/1.1 5xx Fuck You"? Absolutely ridiculous.