My favorite item is definitely the Derelict-Purple Crystal. It's the only CM crystal I actually like (so far), since I've always hated the Black-Color crystals and I'm not a fan of Color1-Color2 crystals either. I also like the Kolto Tank, the Holo Instruments, the Cathar Honor Sword, the 2 Assault Cannons and a few other items, but there's nothing I really must have.