If you have a .NET Smart Client application with a WCF or Web Services backend; the .NET Caching Library is a must have. Cache data on client machines using back stores of SqLite, VistaDb, MS Access or files. The .NET Caching Library also supports distributed caching of ASP.NET Web Farms using SQL Server or Oracle as a back store. Features include asynchronous saving, deleting, expiration, and encryption. Super easy to configure and use. Also supports Silverlight and Windows Phone.