Let me know when they wear out. I'll be a few thousand miles behind you.

I recently wore out the large chainring on one of my bikes. With the gearing on that bike I tended to use the large ring almost exclusively except on very steep climbs, so almost all of my miles were using that ring. It first started giving me problems at 60,000 miles at which time I flipped it over to put the stress on the other side of the teeth. At a little over 90,000 miles it again started to cause problems and I replaced it.

...I never was able to lick my way to the center of a tootsie pop.

Chainrings last crazy long as long as basic chain replacement technique is followed. Let a chain get outside of accepted specification and the chainring wear rate will increase. The further the chain wears the faster it damages the chainwheel and cog. The smaller cogs are more susceptible to the wear as there are fewer teeth to share the abuse and spread out the forces but as chains get really bad the wear on the front chainwheel will accelerate.

The less everything meshes and fits together the longer the sprocket teeth will last. the further out of spec the chain gets the faster the wear on the sprockets. I really doubt people getting 60-90k out of their chainwheels are pushing chain replacement intervals into the danger zone.

The ring lasted longer than the timing belts on my cars !

Timing belts don't "wear out." At least that is true for the 99% of the people who wise replace them on the mfg's maintenance schedule at half or less of the danger zone where any wear could be detected. They are always "perfectly fine" until that instant that they are not.

Yes, mine was 'not' at 144,000 miles at which point the car coasted quietly to the curb. Waiting that long added the cost of a tow to the repair, but was still much more economical than replacing it at 60,000 and again at 120,000 miles. Of course the economics would be very different for the case of an 'interference engine' where loss of the timing belt results in the pistons contacting the valves and doing considerable internal damage.

Pic? That's the sort of item I'd hang on my wall, as a trophy.

Very few newer cars are non-interference design. Without overlapping valve/piston clearances it is hard to get the kind of performance/efficiency standards required in today's low-emission vehicles.

Changing a timing belt isn't necessarily expensive. It's a labor intensive job but not very difficult if you have the right tools and knowledge. But the parts usually run well under $150 -less if you have a high-volume older car. I think the last time I did my '94 camry the parts were under $100. I do it every 90k and it the only real expense the car gives me other than oil/filters, the occasional brake job, tires and a battery every 7-8 years.

I'm only halfway to the 360,000 TB change on the current belt. I might do the water pump this time too. Those are pretty cheap anyhow and don't add too much more labor. I just replaced the rear struts and mounts as well as the sway bar bushings which cost me just a hair over $160 to do myself. That is going to probably push my yearly maintenance budget of this car up over the $200 level for the first time in a decade.

First of all, IMO engine timing belts that require periodic replacement are an abomination in the realm of internal combustion engine technology. The mechanical element that ensures coordination between the rotating/reciprocating assembly and the valvetrain should be designed with an indefinite life expectancy, or at least one commensurate with the engine's bottom end. However, the bean counters, allied with the NVH experts, already have prevailed in many cases.

To design an engine with a known and likely (timing belt) failure mode that will cause secondary, catastrophic failure (piston/valve interference) is, IMO negligent on the part of engineers, albiet in obedience to management.

Now if you have one of these failure targeted vehicles, and knowingly elect to await the failure instead of performing the scheduled maintenance, I'm at a loss to understand the rationale.
The direct cost as well as inconvenience of allowing this to happen at a time of Murphy's choosing could be staggering. Family road trip hundreds of mile from home? Driving to job interview or new job? Evacuating from a disaster?

Since I do my own auto maintenance, on the one vehicle that happens to feature one of these abominations, I replace the timing belt on or ahead of schedule, and especially any time that I'm doing any other work that exposes the timing belt for easy replacement. It is only a $10 part, and is about a 30 minute job from the word go. That's part of the shame of it, it is cheap and easy to replace (as well as expected to fail) like spark plugs, but is a much more mission critical item in that, unlike spark plugs, it gives no warning before leaving you stranded on the side of the road with a expensive tow and/or repair.

Sorry for the thread hijack, I guess I was provoked!

That is totally incorrect. The weight and complexity of a timing chain is not beneficial towards engine performance. Gear-driven cams would be better but are often noisy and not at all cheap in comparison. Putting a timing chain on a high-RPM 4-cylinder engine would be an engineering mistake -not just an affront to the bean-counters.

It's not that hard of a job to change anyhow, and not that expensive. Even after replacing it a few times it still saves money in the long run for the consumer.

I'd like to see where you are sourcing $10 timing belts. I need to maybe stock up on them!