The first two irregular toroidals that I posted were done entirely "by hand" -- which is a fun challenge in itself, involving finding a solution-path as part of the process. However, I just now installed Ruud's SumoCue program and used it "interactively" to make this one ...

(Here's a black & white version. )

It has exactly one solution according to SumoCue, but I haven't yet found a nice solution-path for it.

The following will paste directly into SumoCue ...

SumoCueV1

=0J0=0J1=0J1=0J8=7J2=0J2=0J3=0J3=0J3

=0J0=0J0=0J0=0J6=0J4=5J4=0J3=2J3=0J3

=0J6=0J6=0J6=0J6=0J4=0J4=9J3=0J3=0J3

=0J6=5J5=0J5=0J5=0J5=0J4=0J4=3J4=0J6

=0J6=0J7=2J7=0J7=0J5=0J5=0J4=0J4=8J6

=0J8=0J8=0J7=0J7=0J7=0J5=0J2=0J2=0J8

=0J1=0J8=3J8=0J7=6J7=0J5=0J2=0J0=0J1

=0J1=0J1=0J8=0J8=0J7=6J5=0J2=0J0=0J1

=1J0=0J1=0J1=0J8=0J2=0J2=0J2=0J0=0J0

A cute fact about toroidals: In a plane tiled with a toroidal sudoku, every 9x9 subgrid is the "same" toroidal puzzle.

[2007-04-05: Updated link addresses.]