Amazon offers Prime members the Norton Internet Security 2014 3-User for Windows (pictured) for $18.99 with free shipping. (The download version is available for the same price. Non-members can spend $35 or more to qualify for free shipping; otherwise, it adds $4.48.) That's a buck under last month's mention and the lowest total price we could find by $21. This software scans your PC to identify and eliminate online threats by blocking phishing sites and keeping track of your usernames and passwords so they can't be stolen.

Also available for Prime members is the Norton Internet Security 1-User for Mac for $18.99 with free shipping. (A downloadable version is also available for the same price.) That's the lowest total price we could find by $25, although we saw it for $16 less last fall.