Caching is absolutely the most effective way to speed up the performance of an app. However, .NET does not have a reasonable tool for caching data, such as the contents of a database table, across all servers for all users.* There are third party tools that do this, but they are pricey.
A tool called AppFabric is available from Microsoft (for free) that spans the cache for all users across all web servers in a farm/garden/cluster. Downside: it’s only available for current operating systems like Windows 7, Vista, and Server 2008.
If you’re interested, here are some tutorials:
http://msdn.microsoft.com/en-