A big bunch of price drops on Donald E. Westlake titles, mostly to $1.99, both non-series and Dortmunder books. Titles at Kobo are coupon/VIPable. Most have been on sale before, so check carefully before you buy. The links are a little messy, but I'm in a hurry and don't have time to totally clean them up.
Kindle US:
http://www.amazon.com/gp/search/?sea...price-asc-rank
Kobo US:
https://www.kobo.com/us/en/search?Qu...9&fcmedia=Book
I love a lot of Westlake's book titles, and even have a couple on my "best title" list:
Spy in the Ointment;
God Save the Mark;
Baby, Would I Lie?