Hi Dilip,
I have been thinking about how to do this as I have been thinking of
doing the same....though I am coming to the conclusion it is probably
best to have one server per customer.....

However, my thoughts on the subject were as follows...

1. Set up links or domains for each customer.
2. repoint the domains into a single dot net nuke portal (I am
considerign using dot net nuke www.dotnetnuke.com) as the 'BI portal'
for clients.....probably a release 2.0 thing for me now.
3. User signs in or can now use integrated security for DNN but if you
have multiple companies on one server you are probably going to host
the server outside their security domains so you need a way to securely
log them into DNN.
4. Present reports inside the DNN environment which will allow you to
have the users looking at the one IIS server and one database without
each customer knowing about the other......you control where the users
point to for each report or directory so you can just set up different
directories for different customers.

5. You could even set graphics etc from the userid or portal you were
looking at so the clients saw different formats etc inside their BI
portal...

Having played with all this...I thought it was easier just to get the
clients to pay for one machine each...

Peter