Summer dining al fresco in downtown Minneapolis just got faster and cheaper.

Street-food vendors like the Smack Shack, the Chef Shack and Turkey to Go have been popping up on downtown corners and in parking lots since this spring, when the city gave the thumbs-up to mobile food trailers and carts that prepare food on-site. At most of them, a filling lunch can be had for $4 to $6. Previously, only carts that sold pizza, hot dogs, popcorn and prepackaged foods could get permits.

Several food trailers have been approved, including Turkey to Go, which opened Aug. 3 at 8th Street and Nicollet Mall. The Smack Shack, serving up po' boys and lobster rolls, is open late into the night. The Brothers Deli's cart -- which beckons customers with the slogan "You Gonna Buy a Sandwich ... or What?" -- is slinging some of the longtime downtown restaurant's most popular items. The sun-yellow Dandelion Kitchen, which has been dishing out affordable locavore gourmet items at farmers markets, will soon be parked on the Nicollet Mall outside the IDS Center. Some carts make the rounds of farmers markets, downtown St. Paul and Nicollet Mall.

The new generation of meals on wheels has been proliferating in cities such as Portland, Seattle, Tallahassee and Atlanta, thanks to citizens' increasingly mobile lives and an economy that embraces inexpensive eats. And they're selling a wider, more sophisticated variety of delectables than traditional hot-dog-and-chips fare, from fish tacos to Korean-Mexican fusion cuisine.

St. Paul, often considered Minneapolis' sleepier sibling when it comes to trends, has been out front on street food, and has more relaxed rules, allowing vendors to park anywhere they can plug a meter.

Many local street-food vendors are on to another national trend -- using social media such as Facebook and Twitter to let their customer bases know where they'll be and to lure them in with secret specials of the day. Word of mouth is big, too: One particularly enthusiastic and influential customer, Minneapolis Mayor R.T. Rybak, tweets about his food cart visits. (He's been to the Brothers at least three times.)

Turkey to Go specializes in the same marinated, grown-in-Minnesota turkey sandwiches that it sells from a booth at the State Fair. Judy Saysouriyosack, who works at the skyway-level Verizon store overlooking the turkey trailer, was excited to see the sandwiches she loves being served right under her nose. "I've been tweeting about it all day," she said.

The turkeymobile has a secondary location on 6th and Hennepin, where it'll be parked before Twins games. The other food carts and trailers also already have -- or can -- apply for second downtown locations.

That's the advantage of mobility -- you can go where the crowds are. As long as you've got a license to grill.

Kristin Tillotson • 612-673-7046