Distrubuted Cache platform for ASP.NET

I've got a .NET website and an API interface which sits on top of a VPS (Virtual Server). They both use ASP.NET Caching system (which is pretty nice and comfortable). If it matters - the API system will be ported to WCF at some time.

I want to get ready to move from 1 VPS to multiple VPS (开发者_高级运维when we grow bigger) - thus I need some distributed Cache System.

Ideas would be much appreciated :)

Thanks!

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There are several products that provide this, some open source, some commercial. My personal preference is Microsoft's AppFabric Cache (which is free).