You can aggregate feeds to create the list of messages you want, which is great. However, when creating an export, you might wish to make a custom selection of which messages to export.
There seems to be no way to select more than one message at a time, and I think it would be /tremendously/ useful and as far as I can tell, not too difficult to implement?
This would allow you to create an export rtf/pdf/etc of a few messages you think might be worth printing off etc etc...
Please open a feature request on multi-selection support in the newsheader table. Should not be too difficult to implement, compared to multi-selection in the favorites tree where different elements exist.