What is the best automotive tire repair kit (replacing a spare tire)?

I know many people who absolutely swear by these previously reviewed Tire Plugs. They may not completely rid the need for a spare tire, but they are affordable enough that they are worth carrying around in the car in case you get a flat and can't get to a body/tire shop locally.

Jason, that may not be such a great idea. If you've got a leaking tire because of a punctured tread (not sidewall) or bad bead seal, there are a number of products- plugs, compressors, tire pumps, sealants, etc.- that can help you out, but most of the tire failures I've encountered on the highway were beyond fixing with any kind of repair kit. I don't know how much you hope to reduce your gas consumption by carrying no spare at all, but if you're dead set on it, the best tool for you might be an AAA card,

Super expensive run-flat tires, maybe? How much driving are you doing that you expect significant savings from taking 30 pounds out of the vehicle? You'd get the same weight savings by not filling your gas tank all the way and leaving 6 gallons of airspace.

Also, how far away from major interstates do you drive? Like Dave said, #1 tool for your situation would be roadside assistance, but that didn't help me coming back from Burning Man last year; stuck on state road 447 in the NW corner of Nevada w/ no cell signal.

Former tire store manager, tire man, & auto mechanic. Not currently in any of those trades.

Run-flat tires typically add more weight and subtract more gas mileage than carrying a spare. The technology is evolving, though.

Tire plug kits (which you absolutely should carry and learn to use) only work on tread punctures - they do not work on sidewall punctures, concussive blowouts, shifted belts, or large tread penetrations like slashes or tears. Get a kit at Pep Boys or a similar outfit.

Canned "Fix-a-flat" spooge doesn't work on anything that could not be better fixed with a plug. In addition, tire mechanics HATE it when you use that junk - when they try to work on your tire, either it will be glued onto the rim (if the stuff is completely dry) which makes both removing the rim and seating a new tire difficult, or the stuff will still be liquid, which will result in the tire guy getting splashed with a pint of nasty rubbery glue when the coates machine breaks the rim free. If you use that crap, ALWAYS TELL THE TIRE GUY when you inevitably have to have the tire worked on professionally. If he knows, he can dodge the splashing goo, if he doesn't, he will hate you and may do a poor quality job in revenge (if he is a petty person).

Tubes and patches require removal of the tire from the wheel. The tools to do this in less than half an hour weigh more than a spare and an inexperienced person can easily tear the tire bead (I can do it with a pair of heavy steel tire spoons, a shorty sledgehammer, and a strong compressor - but I am physically large and have thousands of hours of experience).

In short, the other posters are right. The only real substitute for a spare is a triple-A card, and that only works if you don't take long trips and don't travel into areas where there is no phone coverage. Carry a spare.