Rasberry PI
Well my bombed up Linux contractors 386 laptop went to the wind after saving the day many a time. I think the record was 2000 users hanging off it for email along with 200 print Q's.
Boss getting charged a ridiculous amount for email.
Was thinking a couple of PI's and couple of usb drives should be good enough to hang 100 folk off including a web interface.
Job done for 150 quid and an internet connection.