I have quite a bit of rare stuff but i cant remember all of it most is packed away.
Off the top of my head
Panzer Dragoon Saga
Radiant Silvergun
Guardian Heroes
DC ikagura, actually have a shitload of import DC games. Not sure how rare those are...
All the import saturn capcom fighting games with the cart... Streetfighter vs Xmen etc
2 boxed samba de amigo maracas
Herzog Zwei (mint in box unopened)
About 100+ boxed with manual sega master system games. 3D glasses, trackball controller. Im sure some of that is rare. Like a boxed Phantasy star with manual.
Lunar sega cd
Im sure there is more, one of these days I will open the boxes and revisit it