Visual Studio Welcome Screen
Today a colleague noticed that whilst he was debugging his web application random requests were being made to Microsoft, these requests were also returning a HTTP/1.1 301 Moved Permanently header, and apart from being annoying was causing him a few issues.
From experience I soon realised that these requests were being made by the Visual Studio Welcome Screen. By default even if you don't use the welcome screen, Visual Studio keeps the Start Page News Channel RSS Feed up to date, the default in every 60 minutes. If you aren't using the welcome screen then its probably worth disabling the RSS feeds auto download content functionality, not only will this stop you seeing random requests, if you even notice them, but if you are working on a mobile and pay per KB save you some bandwidth.
To disable the auto content update simply: goto Tools > Options, click the Show All Settings checkbox, then under the Environment leaf find Startup. Once here simply untick the "download content every" check box. You can also configure it to update less frequently, alter the news channel location, for example you may prefer to use the DotNetShoutOut RSS Feed.