Notable games released in Japan AND Europe but NOT the US...

[marurun]

Mega Man: Wily Wars on Mega Drive.

Mega Man 1, 2, and 3, with revamped graphics, redone music, and play control that's just SLIGHTLY off for some reason.

[Hobie-wan]

Super Fantasy Zone and Alien Soldier for MD.

[hashiriya1]

NES/FC:
Ghostbusters II
Parasol Stars (?)
Road Fighter

SNES/SFC:
Dragon Ball series
Parodius
Pop n Twinbee
I think there is some hockey game, too.

Mega Drive:
Ball Jacks
Dragon Ball
Mega World
Wrestle World
Zero Wing

[Nemoide]

Shenmue II for Dreamcast.
Americans have it on Xbox but without being able to import the save from the first game, some of the magic is lost!

[Hazerd]

MOAR PICTURES!!

[Xeogred]

Mega Man: Wily Wars on Mega Drive.

Mega Man 1, 2, and 3, with revamped graphics, redone music, and play control that's just SLIGHTLY off for some reason.

Wait, I swear I played this on the SEGA Channel back in the day. Was it just on that service over here for some reason? Wonder if there were other cases like that.

[Aar1012]

Mega Man: Wily Wars on Mega Drive.

Mega Man 1, 2, and 3, with revamped graphics, redone music, and play control that's just SLIGHTLY off for some reason.

Wait, I swear I played this on the SEGA Channel back in the day. Was it just on that service over here for some reason? Wonder if there were other cases like that.

It was only released via the SEGA Channel in the US. I've debated if I wanted to get a reproduction cart but haven't actually done so.

[tintinmayo]

PS2

Naruto Shippuden: Ultimate Ninja 5 (PAL) / Naruto Shippuden Narutimate Accel 2 (NTSC-J)



It's not the best choice if you're looking for a deep fighting game (there's one button for attack, one for special, one for super, and one for jump) but it's all shiny and fun if you're a fan of the franchise. Although I could have done without the tag system. I never liked strikers/tag helpers in one on one fighting games.


Saint Seiya: The Hades (NTSC-J/PAL)



A 1 on 1 3D fighting game. Like the Naruto game above, it's not the deepest of fighters (you can actually just mash a single button and win against even the highest difficulty CPU AI) but it's enjoyable if you're a fan of the series. It looks really good for its time.

Saint Seiya games - specifically the ones handled by Namco Bandai - have a long history of being released only in Japan and EU territories, although I haven't googled enough to find out the reason (probably licensing issues?). Anyway, this entry on the PS2 is the last one to get that treatment as the latest installment, Saint Seiya: Brave Soldiers, will get a North American port.

[Menegrothx]

DBZ, Parodius and Keio Flying Squadron 2 on Saturn (wouldn't call any of those "a notable game" though). I'll give a second mention to Pop n Twinbee rainbowbell adventures because it's an underrated platformer

[dunpeal2064]

One that comes to mind is Whirlo (Xandra no Daibuken [sp]) for the SFC. Its a pretty strict little platformer that doesn't allow for many mistakes, but I actually became really fond of it after Mjmjr25 recommended it to me back when I first joined up here.

I'm not sure if it qualifies as "notable", but Whirlo seems to be somewhat of a collectable, so maybe it qualifies.

Also, the Fatal Frame 2 (Project Zero 2) remake for the Wii was NTSC-J and PAL only, although it being a re-release of a game that already came out here may make it unsuitable for this list.