Answer: This probably means "wouldst thou drink vinegar?" as
aisel in Anglo-Saxon means vinegar. Some commentators
think eisel refers to a lake somewhere in the Scandinavian
peninsula, but as no such lake can be found, or rather,
appears to have been found, it is safe to rely upon the other
explanation. The meaning seems to be "Would you do a
monstrous thing, an impossibility? I'll do it, too, and more
than that."
Mertins, Emma. Shakespeare Examinations. Ed. William Taylor Thom, M. A. Boston: Ginn and Co., 1888. Shakespeare Online. 10 Aug. 2010. (date when you accessed the information) < http://www.shakespeare-online.com/plays/hamlet/examq/seventeen.html >.