Today's technology deal that you should know about is at Cisco Press. Every day they select one book and sell the electronic edition of it for $9.99. Lately they've been rotating between the certification books needed to earn your CCNP (ROUTE, SWITCH, and TSHOOT). Today is a bit of a changeup. Enterprise Network Testing is the deal of the day right now.
When they first started the promotion, some of the books had some DRM bullshit, but now they're just watermarked PDF's, perfect for copying to your Kindle or smartphone.