To cut a long story short: As part of an online database access system I'm writing I want to use the new BLOB access features in SQL 2008 - this means I have to use Windows Authentication when logging into the SQL Server; however due to it's very nature the website front end to all this uses Forms authentication with the membership data stored on that SQL server.
How do I get the web application to impersonate a user account so it can connect to the SQL server, i.e. I don't want to use the account of a user logged into the website. (Not that you could do this as the membership details are stored on the SQL server)
The webserver and the SQL server are on different machines on the same network, there is a user account set up just for the web application to use.