If you like Riak, there is a .net client library. There is a .net port of lessCSS. RabbitMQ works with .net. You can access postgres with .net. I didn't see any

If you like Riak, there is a .net client library. There is a .net port of lessCSS. RabbitMQ works with .net. You can access postgres with .net. I didn't see any features of Neo4J that I can't do pretty easily with MSSQL and a custom DAL. You can talk to Hadoop from .net. I've been using jQuery with ASP.net since it was released. Elasticsearch runs on windows, and I don't see why you can't use it with a .net project. I don't really see the point of pygments, but it looks like it's pretty easy to use with IronPython. So in those instances you have a choice. You can use those libraries/products as they stand, or you can roll your own.