For those who missed the huge Ed McBain sale at Amazon a while back, 31 (assuming I counted correctly) of his 87th Precinct books are on sale again today only, for $1.99 each, as part of the US Kindle Daily Deal.
For those who aren't familiar with Ed McBain (pen name for Evan Hunter), he was a master of the police procedural, and won both a Grand Master Award and a Diamond Dagger. A link to the old thread about the previous sale with info/discussion about the books is
here.
There are also 19 other mystery/thrillers on sale, although I didn't find many to like/buy, since most appear to lean more towards the thriller than the mystery, at least from the blurbs, and I'm not big on thrillers.
I'm not going to provide a link since arcadata usually does in his/her affiliate thread, for those who don't mind giving her/him the affiliate referral fee, and presumably we all know how to find the Kindle Daily Deal anyway.