In Visual Studio 2008 and earlier versions, a line paste retains the caret's current column location. Visual Studio 2010 moves the caret to the start of the line, which is very frustrating. This extension fixes the bug, which has been reported here: https://connect.microsoft.com/VisualStudio/feedback/details/572326/line-copy-paste-bug
Visual Studio 2012 does a better job but it still requires this extension to fix all the cases.