"In DotNetNuke (v3.2.2) is it possible to restrict the number of times a specific user login can be used at the same time.  E.g We want to restrict the use of user 'xyz123' to a maximum of 10 logins at any one time.  As an alternative, we could restrict all users to only one login at a time and create 10 different logins, but this is not the preferred route.  This would need to be configurable on a per user login.
Regards
Roger Graham"
   -- http://forums.asp.net/thread/1321587.aspx

Restricting concurrent logins would be nice!  Question:  How many software-as-a-service packages revolve around this type of licensing--Answer: MOST. 

Business cases might include limiting the number of concurrent logins per user or per portal.  Say our client wants fifty people to have access to a machine-taxing business resource, but is unwilling to pay for dedicated hosting.....so we limit them to ten or maybe twenty concurrent users per portal.  This gives them some negative feedback (almost any system without it will destroy itself), and helps them realize "business costs" that begin to make dedicated hosting seem to be a more reasonable expense.  Limiting this way also helps keep one portals' users from devouring so much of the host that all other portals appear to be slower than contracted or flat out under a DoS attack...

Robert