I'd still be temped to find away of giving whatever security context your web request runs in to have enough rights to kick of a new process, but agree that this may have potenial security implication.

BUT I had another brain wave check out "rotor" the shared source implemenation of the .NET framework comes with an implemenation of sn.exe.

This artical gives an overview of rotor:
http://msdn.microsoft.com/msdnmag/issues/02/07/SharedSourceCLI/default.aspx

Download it here:
http://www.microsoft.com/downloads/details.aspx?FamilyId=3A1C93FA-7462-47D0-8E56-8DD34C6292F0&displaylang=en