Stamps and Stationery
Mewtwo notepad

This was one of my more recent additions - it was paired by a Bulbasaur notepad of the same style.
Mewtwo Pencilboard #1

A nice pickup that came from one of the Pokemon Centers - I believe this is the same pose for Mewtwo that's used on the Mewtwo trash can that I'm hunting for.
Mewtwo Pencilboard #2

This one's from Banpresto - nice that Mewtwo was fully featured here, though admittedly I like the Mewtwo style on the other pencilboard better.
Mewtwo/Mew folder

I remember these being common a while ago, but as many of them fall apart from use, they're getting rarer. (Mew's on the other side, obviously.)
Giant Carlton Cards Bag

This thing is...huge. And well-worn from its previous owner, but I'm just glad to have it. It also reminds me why I don't usually buy stuff from greeting card stores - oversized bags, cards, or anything like that are expensive as hell!
First Movie Promo Stamp Pin

It's both a stamp and a pin, but the Mewtwo part is in stamp style so it went in with the stamps. Didn't see any of these for years, but then they started showing up on Y!J and eBay at fair rates. I think I paid 500 yen for this; the eBay ones are being listed at $34.50.
Fancy Japanese pencil

These were wrapped in individual sleeves - I remember paying a premium for this one, and if I had more than a couple of 'em I'd actually use one.
Stock art pen

Picked up a couple of these in a multi-pack; it also included a few of Pikachu with a red background.
Stock art pencil

I may not use the other pencil, but I'll damn well use these - I picked up about 30 of 'em in a bulk lot a long time ago. Dirt cheap, too. Oddly enough though, I haven't seen any for sale anywhere since.
Mewtwo Stamper

One of many Mewtwo stampers I've picked up over the years - just need to get some ink for him!
Tiniest Mewtwo stamper ever

This picture make this thing look a lot bigger than it actually is. It's probably about the size of one of my fingernails, if that.
New Stamper

Picked up around Movie 16 release.
Original opening sequence postcard

One of many Japanese postcards I've seen over the years. This one's a bit sentimental - if your first experience with the Pokemon series was with the anime, and you watched an episode from the beginning, Mewtwo was the very first Pokemon you ever saw. You never forget your first.
Kenshin postcard

This postcard's much more recent - from the Pokemon Conquest series, Mewtwo partnered with Kenshin, an honorable fighter who seems to be the perfect fit for him.
Banpresto postcard

One more oldie but goodie - Not a bad picture of Mewtwo on this either.
Mewtwo...postcard? Other stationery?

This one must have been way old - it only has a hint of Mew's existence.
Shogakukan stamp

The first of many Mewtwo stamps I've picked up.
Shogakukan #2

Another from the same series...
Shogakukan #3

...and another...
Shogakukan #4

...and one more. Some, but not all of these came from Cheshire-Kat.
Tadjikistan Stamp

If there were Mewtwo stamps over here at $4+ value, I would have been using them on my shipping for damn near everything!
?????

(Like with any of the other items I've listed of unknown origin, if you know where this came from, please let me know.)
Pokeball and Master Ball Mewtwo Stampers

Same image, I believe, two different toppers. Maybe there's a Great and Ultra Ball in the same series?
Tiny imported stamper

This had to be one of the smallest things I took a picture of, which made it difficult to get a good shot...
Stamper side view

...especially when I had to use another toy to prop this up to get a good picture of it on its side.
Pencil topper #1

This is, I believe, the most recent pencil topper/toy to come out.
Clear Topper

One last bit of stationery in this section, with both the see-through...
Standard Topper

...and standard version.