Share dataset between two ASP.NET applications

In other environments, I would recommend sockets. There are some great socket libraries out there that make it really easy and sockets are about as fast as a network gets. In .NET, you also have some great socket classes (tcplistener). If the transmission is relatively simple, this can still be best because it doesn't require an HTTP server like web services. Otherwise, .NET really makes webservices easy to use and hard to resist. It's much easier and much faster than other implementations of SOAP and XML-RPC. It also provides .NET Remoting, which is a very cool rip-off of CORBA with advanced features. It is very fast, but not as easy as web services. If it's not a big deal to have a web server involved or if the transactions are complicated, web services are the way to go. Memory-mapped files, mailslots, named and anonymous pipes aren't really supported in .NET (yet).

I have a similar problem (I posted also in ADO section without viewing this thread, sorry for cross-posting), I have to share a dataset between two applications at runtime, I should care about speed in particular, and disk space too. Wich is the best solution, socket named pipes or web services? In general, how can I share data (ex. variables) between two application without using a tcp listener with sockets?

You want to share datasets without using a database? Datasets were designed to use data without a database, but they were designed to use XML instead. You could do this some other way, say, an in-memory ISAM table or a multi-dimensional arrayor something, but these things wouldn't necessarily work any better than XML. XML can be used without saving it to a file, too. You can send XML datasets across sockets, SOAP, named pipes, mailslots, RPC, etc. Any of these would work (I'm not sure yet how to do some of these in .NET without Interop). What is your concern? Latency? Disk space? Parsing difficulty? Code simplicity? Speed?