Here's an Anglo-Saxon riddle (from the Exeter Book MS)? (Also a chance for some of you to see what English looked like back a thousand years or so.)

Ic on wincle gefrægn     weaxan nathwæt,
þindan ond þunian,     þecene hebban.
On þæt banlease     bryd grapode,
hygewlonc hondum,     hrægle þeahte
þrindende þing     þeodnes dohtor.

I have heard of a thing, waxing in a corner,
swelling and standing up, raising its covering.
A proud woman seized that boneless thing with her hands;
the lord's daughter covered that swelling thing with her dress.
[translated by F. H. Whitman]

What is it?