Collecting CD and shirt is not simply buying. Most of collectors know how important to get completed discography of cool bands and full set of single CDs, concert edition, posters, etc.
http://sofiametalqueen.deviantart.com/gallery/35426590
https://www.facebook.com/media/set/?set=a.223369381050039.69455.126541410732837&type=3
Getting of shown below collection of Dimmu Borgir CDs & shirts FOR FREE was really cool, haha
More collections - metal bands : Slayer, Metallica, Sepultura, etc