We have this discussion frequently in economics classes about how to allocate scarce resources, where the example is either seats in an economics course or (the perennial favorite of faculty) parking. All goods get allocated, we teach our young charges, it's just a matter of what you use as the allocation device. Markets, of course, use prices.

Some people have a problem with that. Laura Billings would be one. And Mitch Berg does a beautiful satire thereof. Laura tries out her reductio ad absurdum trick bag.

Say you're at the grocery store after 5 p.m., and every checkout lane is backed up to the bread section, all except for the "10 items or fewer" express lane. For a reasonable premium, you ought to be able to haul your 116-item cart up to that register and speed right through.

As Mitch points out, there's always been delivery, as well as convenience stores (thus the name, right?). And let's not forget PeaPod. Another thing we teach, Ms. Billings: Substitutes abound.

how about when you get to the movies right during the trailers only to find out that the theater is practically full and that there's someone � probably some sad sack who didn't have anything better to do than to get to the movies on time � sitting in your favorite center aisle seat. Well, for a convenience surcharge on top of the regular price, you should be able to bypass the ticket line, have the kids at the concession stand hand you your pre-ordered popcorn and Jujubes, while the ushers move the guy who got there before you over to another seat, right against the wall. If you paid a little more for the privilege, that's fair, right?

Laura, have you ever seen Jack Nicholson at a Lakers game? Where do you suppose his car gets parked? And in case you didn't notice, there are people who bring drinks to you down there, rather than having to schlep to the concessions.

Just imagine how wonderful our lives would be if we could store up all of this privilege on a little electronic convenience card.

Um, smartcards?

You could swipe it and bypass the hour-long line for the ladies' room at Dixie Chicks and Norah Jones concerts.

You're not going to like this, Laura -- they're thinking about it for the new sports stadium. According to the Metropolitan Sports Facilities Commission, they're already doing this at Safeco Field in Seattle. And you should check out the .300 Club at Bud Lite's new Miller Park in Milwaukee. For $500, you dodge the bratwurst lines with the hoi polloi.

You could flash it and move your kids to the head of the waiting lists of the selective colleges they didn't quite make it into.

That used to be called "alumni contributions". Now it's called "affirmative action."

Laura, take a bite of a reality sandwich. We'll move you to the head of the line.