Intranet/Portal software recommendations

[Terence K. Huwe]

Friends-

My research institute is (finally) going to get to work on intranets,
extranets, and hopefully, portals.  I'd like to query this list for two
sets of recommendations.  Given the need for broad-based info-sharing, I
think everyone should respond to the list instead of to me--I've learned so
much be reading discussion threads in that manner.

My request for recommendations are:

1.  What intranet/extranet software do you recommend? (MS IIS and Exchange
Server on hand, but we're not attached to that route)

2.  What technical specifications (size, ram, bandwidth, storage etc) do
you recommend for 
a server that might host 3 intranets plus administrative file management
needs?

I would greatly appreciate some responses by next Monday if at all possible.  

Thanks a lot!  Terry Huwe/IIR