Plenty of things.

While not worthless, I still have a large collection of Nintendo Power magazines, which I still thumb through every now and then.. A lot were ones I I had from my subscriptions, but also a fair amount I later E-bayed.. Most of them in the issue #1-130ish range. I plan to try and make a complete collection of 1-100 someday.

Also, plenty of misc similiar guides, such as the old NES TOP SECRET guide, and the one for the Super Game Boy and SNES, and various players guides and instruction manuals, some for games I don't even own.

I also have a couple of those VHS tapes that Nintendo Power sent out, which I remember a few being particularly goofy. (One of them was for SF64, with a Sega and Sony guy torturing a Mario doll to get a dude to talk about SF and how great of a game it was. "THE RUMBLE PACK!")

Getting into the stuff that's actually closer to worthless, I also have a lot of paperwork and things that came with my various systems and games.. Very worthless since people want boxes rather than(or with) that stuff, but I keep them anyway.

I have a small Turok: Dinosaur Hunter poster that the folks at Hollywood Video gave me after they were done with it. (I think I might have gotten other things as well, but I don't remember..)

I also have a huge card-board standup with Lugia on it.. It was at a Pokemon card game convention, they were going to toss it afterwards so I took it. (I also bought one of the Pokemon labcoats the staff were wearing since they sold those after, lulz.)

Also, one of the odder things I have.. Way back when, there was a website that was one of the first/only to have this massive section dedicated to the Death Mountain Descent glitches in LttP, with screenshot tutorials. It was very fascinating stuff, and my first brush with truly involved gaming glitches, and to help me in using them since my computer and SNES were in different rooms, I printed the whole damn thing out.

I had an ancient printer, so they were in black and white and very faded looking even when they were new, but nonetheless I loved having that massive stack of pages. The site later went down, but the glitches spread nonetheless, and to this day I still have them in a folder somewhere, although a bunch of pages are missing.