Good ideas for Christmas gifts for sales reps?

As someone who is constantly in his car, I recommend getting small voice recorders for them.

Gives them an opportunity to keep quick thoughts, to-do lists, etc. a place to write them down later, rather than driving while writing.

Depending on your line of business, this also allows them to make a quick "note" about a potential prospect they just passed, or a truck that passed them.

You asked for books:

SPIN Selling, by John Rackham
Customers For Life, by Carl Sewell
The Effective Executive, by Peter Drucker
The World is Flat, by Tom Friedman
What Got You Here Won't Get You There, by Marshall Goldsmith

Merry Christmas

Mark