ScottGu introduced Microsoft's WebMatrix which is a small IDE to make web sites (ASP.NET and PHP). It actually includes everything you need: IIS Developer Express (a development Web server), ASP.NET (a Web framework), and SQL Server Compact (an embedded database). This product is aimed at developers and students who want an easy way to develop web sites. It is emphasized that all the knowledge and skill you gain using Microsoft WebMatrix is applicable to Visual Studio. WebMatrix is a 15MB download (50MB if you don’t have .NET 4 installed) and is quick to install.

Microsoft WebMatrix page
Microsoft WebMatrix Learning page
Scott Guthrie's WebMatrix post
Scott Hanselman's WebMatrix how-to