Well, if you ever wanted some of acclaimed sf/fantasy author Diane Duane's backlist and can choose and checkout within the next 2 hours and 40 minutes, you can save 20% off a purchase of $10 or over when you buy direct from the author at the grand opening of the new version of her self-operated website store.
There was a glitch in the store, so now the sale's been extended to 0001 Pacific Time on June 1st. Full details including the coupon code you need to enter are in
this post on her blog here.
She sells DRM-free and you have a choice of ePub or Mobi (no multi-format, but apparently
the site keeps purchases in the cloud for you to re-download you get a link in your e-mail which goes to a website from which you can download your the files up to five times).
International users outside the US and Canada can get her popular
Young Wizards YA series (you may want to hold off on these; apparently
revised and updated editions will be coming out).
Everyone worldwide can buy her
Tale of the Five fantasy novels (the Omnibus collects them all for a slightly cheaper than the individual volumes and qualifies on its own for the discount) or her short story collection
Uptown Local, which contains some of the stories also being sold as singles, so check their titles against the contents listing.
Just so you know, Duane doesn't seem to normally hold sales or dole out coupons for her Smashwords books during Read an e-Book Week. The last time she did anything of the sort was when she had to
raise emergency money for a bulk purchase of her cat's special prescription kidney-failure-avoiding food.
So if you've had an eye on her rights-reverted backlist e-books, now is probably a good time to splurge, unless you think you can hold out for a likely holiday or the cat food to run out again.