For much of my life, the four weeks before Christmas were jam packed with parties, mostly work related and therefore obligatory, shopping excursions to unearth novel gifts for people who did not need them. For more detail http://www.geoholidayclub.org

1. Geo Holiday Club
I like the variation on the grandfather paradox whereby
you travel back just one hour into the past and shoot
yourself dead. That's a novel way of committing suicide!
The other paradox I like is when you go back in time to
have Shakespeare autograph your copy of "Hamlet".
Shakespeare isn't home but the maid promises to have
him autograph your book when he returns. Alas, your
timing is slightly off and Shakespeare hasn't yet written
"Hamlet", so when he receives your copy from his maid to
autograph, he reads it, and after you return to
Shakespeare's home and receive back your now
autographed copy and return home to your own time,
Shakespeare now writes "Hamlet".
For more detail http://www.geoholidayclub.org/