You should at minimum be able to copy them into Word (maybe OpenOffice?) and save them as an RTF that way....
I don't believe the Reader supports in-line images in an RTF, so it may not be much use.
I don't know of anything that'll give you RTF's straight from the browser, but that doesn't mean there isn't something.
I'm also hoping for an addon like there used to be (and still is) for the Librie' that will let us print directly from a browser into an LRF file that can go straight onto the Reader. For all I can tell at the moment, the old Librie' toolbar thingy will work just fine for the Reader. Won't know 'til I can experiment.