Morty, thank you very much for your helpful comments.
Canadian Tire has a great little kit that combines a compressor and sealant for $49.99. Product # 09-5065-8. Called the Airman Tire Repair Kit. 12V air compressor with Dunlop sealant to effectively seal a tire puncture. Takes 5 minutes and plugs into the cars cigarette lighter.
Smaller and lighter than a spare.
The only time I have ever had a blowout in the sidewall was when a tire was severely underinflated on an employers truck. I was 16 then, and have since checked tire pressure monthly with a good tire gauge. I have never had a sidewall blowout since. Yes nails and road debris can flatten through the tread, and it is possible to ruin a tire completely from a puncture at highway speeds, but that happens when you're not paying attention.
To those that gave their 2 cents worth of sarcasm, open your minds to something new, and stop cluttering up useful threads with inane comments. Mercedes Benz includes a compressor/sealant instead of a spare in their sporting models that have little storage space.
To anyone out there who thinks for a living, consider this alternative to changing a spare on a 400 series highway or in the dark when you've brought no flashlight and the wheel is rusted in place. Then a quick fill up of sealant and compressed air will get you to a safe place. I'm getting one for the wife and leaving her the spare in her Corolla. My spare will rest at home. In my opinion, they are only a sop to Car company lawyers and those who can't think outside the box. Hey, theres always cell phones and credit cards in a worse case scenario.
I'm predicting now that once tire pressure monitoring systems are mandated in new cars as planned, spares will be dumped and replaced by this type of fix. You heard it here first.