You could taste it and see if it acceptable to use in BBQ basting...but, frankly, if you are into snobbish beering then those beers won't cut it at all. On the other hand, proselytizing beers is often difficult if you are faced by people unwilling to change...and why should they, right? They're happy in their particular beer bath for reasons known only to them...and popular culture.

"alas I don't have the money to build a cellar or the willpower to let beer sit nearby without drinking it. "
LOL! That's my problem too...
Luckily I have some friends who are mad beer collectors with much more self control (and money) than I have.
One of the best beers I've ever had was DeDolle's 20th anniversary beer (a Flemish Sour) - it was 7 years old and Amazing!
I've had home brewed Ales that were 6,7 and 8 years old that held up just fine.
Ive had Harvey's vintage stouts from 1999, 2000 and 2001 that were terrific too, but ive also had ones that had definitley passed their prime, probably due to how they were stored over the years.
I've seen vintage Aventinus bottles out there too (only a couple years old, but I think they are going to be releasing some every year over the next few years), but have not tried them yet.
The truth is, some beers can take it, some can't. DeDolle (one of my all time favorite breweries) says they celler a portion of every batch of "Stille Nacht" they make and sample them periodically. They say the old ones keep getting better. Ive had a 2 year old Stille Nacht Reserve and it gave me goosbumps it was so good. The problem is, except for the "Special Reserva" line, their beers are not dated so you never know how how old they are when you buy them. How long did the beer wait to leave Belgium? how long did it spend on a ship? waiting to get through customs? in the importer's warehouse? in the distributor's warehouse? in the liquour store's warehouse? on the shelf?

The corona mentioned in the first post probably cant too much aging, but it wasnt any good to begin with, so no real harm done. Things you want to avoid are, light (corona is in clear bottles, so it is extra prone to light damage) and temperature fluctuations, (once you chill a beer, keep it cold untill you drink it)

The beers that can take the ageing and hold up (or even get better) are going to be the BIG BIG beers, especailly the high gravity strong ales. Of course, IPAs were made speciafically to hold up on the trip to India from the breweries in England. How long did that take to make the cruise? Beats me, I'd be interested to find out, but thats why they were stronger and hoppier. Here in the states, we like our IPAs fresh though, with that crisp hop bite and aroma. If you drink a fresh IPA next to the same beer thats been aged a year or 2 you will find the older one will have mellowed out A LOT, the aroma, especially of a dry hopped IPA will diminish pretty quickly and the bitternes will fade over time, but you will still have a perfectly drinkable beer, and probably somthing closer to what the british colonials were drinking in India back when the style was invented (without getting into the differences in the new world hops in our american IPAs and the old world they were using in the days of the "empire")
As maybe you can tell, im bored and rambling on a rainy saturday afternoon, maybe i should go out for a pint...
Cheers!