Please note this has not been extensively tested so I recommend you give it a thorough
trial before using in a production environment.

See my blog post on this project here:

(Current, v1.1.0) http://www.adathedev.co.uk/2013/03/mongodb-aspnet-session-store-provider.html
(Original, v1.0.0) http://www.adathedev.co.uk/2011/05/mongodb-aspnet-session-state-store.html

Notes on use / configuration can be found in the above post, and also in the comments within
MongoSessionStateStore.cs.