Пощу это в философию, а не в Net, поскольку речь в видео идет в основном о монадах, etc. Само по себе к Net это имеет опосредственное отношение — хотя и войдет в Net 4.

Итак, довольно интересное видео:

Erik Meijer and team (developer Wes Dyer, in particular) have created a profound and beautiful .NET library that will take managed event based programming to new levels. Of course, many of you wish that you could write LINQ expressions over events. Well, now you can thanks to Erik's and Wes Dyer's latest creation, Rx — .NET Reactive Framework. Erik, being a fundamentalist functional theoritician, can't create new programming abstractions without employing some form of monadic magic.

Expert to Expert: Brian Beckman and Erik Meijer — Inside the .NET Reactive Framework (Rx)

Buried deep in the bin folder of the Silverlight Toolkit Unit Tests is a hidden gem: The Rx Framework (System.Reactive.dll). If you glanced quickly you’d miss it altogether but it’s one of the most exciting additions to the .NET framework since Linq.

Introducing Rx (Linq to Events)


Для экспериментов понадобиться System.Reactive.dll — которую можно скачать в составе Silverlight Toolkit v3 (исходников и документации там пока нет)