All of the books in the Craft Sequence by Max Gladstone are on sale for $2.99 each including a pre-order for book 6. If you don't have any of the previous books, there's also a pre-order of an omnibus for 1-5 at $12.
Amazon US:
https://www.amazon.com/s/ref=nb_sb_s...tal-text%2C228
Kobo US:
https://www.kobo.com/us/en/search?qu...e-7db73eb49b37
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@Paul
I read Wes Chu's Tao trilogy and thought it was fun too. Haven't read the new Io one yet, but it's in the same setting. He won the Campbell Award in 2015 and had also been nominated in 2014 so books one and two were in those Hugo voter packets.