When my son was very young, I used a baby monitor; one of those old-school radio types. I worked night shift, so I would rush home, snatch a kiss from my wife as she headed off to work, slam some breakfast, vitamins, and a full cup of coffee before my son woke up. Having the receiver next to my bed was VITAL to being able to wake and get involved in his day.
The above-mentioned gadgets? Disgusting. If one could be proven to prevent
SIDS, then I could get onboard with that, but otherwise, no. We are slowly turning our world into a prison; one we purchase for ourselves, brick by shiny techno brick, and insist the surveillance cameras catch our 'good side'. The powers that be couldn't ask for better surveillance tools than the ones we insist we can't live without.
*sigh*
Pardon me, I'm going to make myself feel better by unplugging something.