Ultra Special Editions?

[marxbro]

I recently saw a video of a random guy's dvd/blu-ray collection (it took up an entire room in his house) and he had a lot of what I could only think to call Ultra Special Editions most of which come in special packaging like a Spider-man bust or an Alien egg or big oversized boxes with unique cover art, all of which are hella cool.

I'd like to get into this kind of collecting and wanted to know if anyone can give me some info on how and where to find these special releases. I'd really appreciate it and also if you have any yourself I'd like to hear about what you've got! Thanks