If like me, you design your own book covers, good tools are critical. I use Adobe Illustrator and Photoshop CS5.5.
Now, Google has decided to offer the Nik Collection of Photoshop plugins for free. These are fantastic and well worth looking into. Here are the link and announcement.
Nik Collection: Google Makes $149 Collection of Photography Tools Now Free to Download. Google originally gained the collection when it bought out German developer Nik in 2012 and dropped the price for the tools to $149 from $499.95. Users who paid for Nik in 2016 will be refunded.