Special Edition CD's

I have been noticing more and more bands putting out special editions of their albums. These special editions are more than just a couple of extra tracks, but now include expanded packages and artwork, bonus discs (both audio and/or DVD), and even more extras.

Just in the past few months I got the new CD's from Nevermore, Black Label Society, Disturbed, Iron Maiden, Kamelot, and Stone Sour in special packaging and with bonus material. I was wondering if any one else has been purchasing these and what you think about them.