There is an article on /. about this firmware hack http://slashdot.org/articles/04/05/18/038248.shtml?tid=137&tid=164&tid=185&tid=198[url] Which is supposed to allow some single layer NEC drives have double-layer burning capabilities. I don't own an NEC drive, nor would I likely try this even if I did, but I thought this might be of interest to some people here.

There is a pretty good discussion there of some of the pluses and minuses for such an upgrade, including thoughts on robustness of the burned media (will it be corrupted in a short period of time?)

Also, it looks like you would need a PC to flash the firmware, though I'm not sure about that.

aloha,
Joseph