Perhaps I may have something to contribute (DavidL, try not to fall out of your chair).
I've found iAutomate's RFID hardware and HomeSeer plug-in to be quite useful, and with some tweaks, very reliable. The readers currently being sold are long-range. I'm using them at the moment for macro presence. HomeSeer knows if my car is here or not, where my keys are (relatively), if I'm here or not, and whether my daughter is here or not.
The most useful functionality so far has been with HomeSeer detecting my daughter's presence through her RFID tag. When she's here, almost all of the house routines (HomeSeer events) are altered. Lights, temp, announcements, and other day-to-day HomeSeer stuff are now macroed based on *who* is home. I guess that's kinda like your "super-trigger," Electron. Now, I know longer have to manually adjust events when we get off typical schedule. HomeSeer adjusts real-time. (OK, it wasn't that hard before, one button press in MainLobby, but hay, HA makes you lazy).
Having the garage door open or a gate open and lights or whatever activate when a tagged vehicle arrives is a no-brainer with this technology. Customize the routine based on individual vehicles, time of day, whatever your whim.
If I had a toddler, I'd be all over this for safety reasons. This will be especially important, I think, when iAutomate releases their short-range readers. I'd want to know precisely where that little tike was at all times - what room has she wandered into....You can accomplish this today - somewhat - with the long-range readers by understanding specific RF tendencies in your circumstances. I believe iAutomate's plan with the short-range readers is to make this type of functionality easier to implement.
I plan to use the short-range readers in lieu of motion sensors in my home. More information is gathered...not just motion/presence, but specifically who is where/moving.
This week, I'm adding an electric door strike that will be RFID triggered for custom entry to my home.
At 20ish bucks a tag, it starts to get affordable to add on other types of functionality like monitoring the trash can on trash day, tagging valuable assets, arming/disarming security for housekeepers, neighbors, pet sitters, house sitters.
You could accomplish these things by other means, but RFID has proven to be more straightforward and dependable for me (than say the W800).
Oh, and Squintz, I'd smash your cables too if you put an RFID tag on my vacuum cleaner!!