A reasonable guess: the sudden price drop is due to Sharp blowing out their remaining inventory in preparation for discontinuation. Its consistent with the other moves Sharp has been making lately... They\'re probably going to pull out of the US handheld market entirely. (and let IBM deal with the \"enterprise\" sl-6000. Heck, I would not be surprised if it comes out as an IBM branded product)
No matter what the cause, $299 for a 5600 is not a bad deal.