SQL Search, a free searching tool for SQL Server schema

http://www.red-gate.com/products/sql-development/sql-search/

How to open SDF file, SQL Server Compact file in Visual Studio?

http://erikej.blogspot.com/2010/12/visual-studio-tools-for-sql-server.html

How to change a project type to MVC 3?

Open csproj file from text editor, such as notepad
change ProjectTypeGuids to following setting
    <ProjectTypeGuids>{E53F8FEA-EAE0-44A6-8774-FFD645390401};{349c5851-65df-11da-9384-00065b846f21};{fae04ec0-301f-11d3-bf4b-00c04f79efbc}</ProjectTypeGuids>