4
WF-Section *may* do this, but I haven't got in to play with all it's bells and whistles since about beta 4 I think. The only module I know for sure that supports that functionality out of the box is AMS which I will be releasing as of Monday. AMS has a feature called 'audience level' which basically takes the text in the description area of an article and treats it as a teaser. However, only those who are members of the groups which have permissions to that particular audience level will be able to view the entire article. It's kind of hard to explain, but I am 99% sure it is what yo are looking for. Register at ams.it-hq.org to get pretty much full administrative access (no access to info blocks) of the AMS module and have a go for yourself.
