Can anyone add to this list? (I did not include one-off types that have popped up here and there over the years.) Corrections also welcome. I can post examples of these if needed.

- 9x9 Extra Constraints

- Asterisk

- Calcudoku (Mathdoku, KenKen[tm]; math operation cages)

- Center Dot

- Chess Moves

- Clover

- Consecutive/Non-consecutive

- Diagonal (Sudoku-X)

- Disjoint Groups (Compass; positional colors/groups, Sudoku-P)

- Even-Odd

- Extra Groups (miscellaneous patterns)

- Girandola

- Greater-than/Less-than

- Killer (Sumdoku, Samunamupure; addition cages)

- Meandoku (the mean of two adjacent cells marked as >5, <5, =5)

- ORC (odd rows and columns are 1-9, no repeat)

- Touchless Wrapper (Toroidal Anti-Chess)

- VX (cages with sums to 5 and 10)

- Windoku (Hyperdoku, NRC, Sudoku-W)

Gattai (multiple overlapping grids)

- Butterfly (4)

- Clueless Explosion (10)

- Clueless Special (10)

- Flower (4)

- Harakiri (8)

- Kazaguruma (5; Windmill)

- Kunoichi (5)

- Large Gattai (miscellaneous shapes and sizes)

- Ninja (9)

- Samurai (5)

- Sensei-1 (2, 1-nonet overlap)

- Sensei-2 (2, 2-nonet overlap; Double-Doku, Two-Doku)

- Sensei-4 (2, 4-nonet overlap)

- Sensei-misc (2, miscellaneous overlap; Conjoined)

- Shaolin (25)

- Shogun (11)

- Sohei (4; Ring)

- Sumo (13; Super Samurai)

- Taiken (21; Circle)

- TripleDoku-1 (3, 1-nonet overlap)

- TripleDoku-2 (3, 2-nonet overlap)

- TripleDoku-4 (3, 4-nonet overlap)

- TripleDoku-misc (3, miscellaneous overlap)

- Wing-3 (3, V-shape)

- Wing-5 (5, V-shape)

Irregular Nonets

- Jigsaw

- No Boxes

- No Boxes Disjoint Groups (Plum)

- Toroidal

Large Grid

- 12x12

- 16x16

- Miscellaneous Sizes (7x7, 8x8, 25x25, etc.)

Sequential (Relay, Twin)

Sukaku (Pencil Mark; no givens)