Smashwords.com has an exciting feature for promotion of your book, a Coupon Generator. With this, you can set discounts of your work to a lower list price or even free if you so desire. Simply click on the "Coupon" option in your dashboard to enter the discount. The discount code is generated and the change takes effect immediately.
Here are the discount codes for my books that take the price for all down to $.99 each.
Emily's Unicorn = Coupon Code GF88G
Slipstream = Coupon Code KD88J
Pantera = Coupon Code LV59Z
The codes are not case sensitive and you can enter them when you check out.
Enjoy and thanks for reading.