X-link to the DRM-free megathread since there's also a DIY gadgetry Humble Bundle that the more DIY-gadgetry-inclined sfnal readers may want to try out alongside Wildside Press' Tuesday freebie:
The Jerome Bixby MINIPACK™ by the late Jerome Bixby (
ISFDB,
Wikipedia), a mini-collection of 5 of his classic Golden Age sf stories (he also wrote screenplays for Star Trek, and the classic "It's A Good Life" episode of
The Twilight Zone).