Here's my collection. It's not very large, but I just got into it a few months ago.
2X2X2
V-Cube 2
Quantity: 1
A mass produced 2x2x2 by Verdes. Sold in traditional and pillowed shape and with back and white body.
3X3X3
4X4X4
5X5X5
CUBE (SHAPE PRESERVING)
Rex Cube
Quantity: 1
A corner turning hexahedron. Very similar to the MasterSkewb but without its corners.
CUBE (SHAPE CHANGING)
Bump Cube
Quantity: 1
The Bump Cube is a simple 3x3x3 Rubik's cube, but with an interesting twist. It spawned a whole series of puzzles and created a verb of its own.
CUBOID
Crazy 2x3x3
Quantity: 1
A 3x3x4 with two layers removed but not hidden.
DODECAHEDRON
Megaminx (1999)
Quantity: 1
This is a newer version of the Megaminx, published by Meffert, with tiles and 12 distinct colours.
FOUR