The blogosphere is all a-twitter over a pair of too-good-to-be-true sales announcements this morning. First up, Best Buy 's (NYSE: BBY) amazing offer to sell you a 52-inch Samsung plasma for $9.99. Sadly, that one's a goof. Best Buy posted the wrong price on its website, and refuses to honor it. But the other deal is for real. JetBlue (Nasdaq: JBLU) really will let you fly anywhere in the U.S., as often as you like, for $599 flat.

Dubbed the "All-You-Can-Jet Pass," this deal only runs through August 21 -- so you'll have to act fast. Here's what you get for your $599:

Now, I'm sure some call this is dumb move. All it takes is one smart cookie taking a pair of roundrip flights between JFK and San Diego for JetBlue to begin losing money on this deal. But there are several reasons I like it.

This deal has much in common with similar "all-you-can-eat" offers from salesforce.com (NYSE: CRM), AOL , and Netflix (Nasdaq: NFLX) -- for on-demand software, dial-up Internet access, and DVD rentals respectively. If the concept didn't "work," it wouldn't be so popular.

Also, JetBlue has wiggle room here. No fair hogging reservations -- if you book a flight but don't show up, you pay a $100 no-show fee. (Fare's fair.) You must plan ahead for reservations (something we Americans aren't always so good at.) And there's a limited supply of Passes available -- so JetBlue can cut its losses short if necessary.

Foolish takeaway
On the plus side, consider that a customer "locked in" to the Pass now is a customer motivated to not to patronize JetBlue's rivals. You don't order the salad bar at Pizza Hut , then dodge next door to McDonald's for a burger. And you don't shell out $600 to jetBlue for unlimited travel to then patronize American (NYSE: AMR), United (Nasdaq: UAUA), or Southwest (NYSE: LUV) during that time period. And in the meantime, jetBlue gets use of your money and some extra publicity.

Also, the Pass goes active during a slow time for air travel. Vacations are over. No major holidays on the calendar. Kids back in school. If ever there's a time to get creative with stoking demand, this is it.

Like I said, there are many reasons to like the All-You-Can-Jet Pass -- yet I have room for only a few up above. Now it's your turn to fill in the blanks. Why do you like JetBlue's offer? Where do you see strings attached? Were we too hasty in "selling" JetBlue from the Motley Fool Stock Advisor portfolio? (Read why we did so here.) Post your comments down below.