Here's a link to an article by Roland Anderson at the Seattle Aquarium about euthanizing or sedating octopus in case anyone finds themself in the position of a cephalo-Kevorkian. This was posted on Reef Central's ceph forum, but I thought it was worth sharing.

Drum and Croaker, v.27 1996 (http://www.colszoo.org/internal/drum_croaker/pdf/1996.pdf)