Tea parties are like prom for some activists: It's all about the outfit.

But instead of a trip to the local mall, tea partyers surf the web to find those colorful tees with one-liners like a grinning George W. Bush asking, "Miss me yet?"

Do-it-yourself T-shirt design shops like Cafe Press and Zazzle have noted an uptick in anti-Obama gear this year. The sites let anyone upload a design and try to sell it for a share of the profit. The company takes care of the printing, payment processing, and returns.

While the sites really took off during the 2008 campaigns -- when Obama shirts were a hot commodity -- it's the conservative gear that sells now.

"We've become a cultural barometer of what's going on," Cafe Press spokeswoman Amy Maniatis said. "These are folks who are going to be wearing their passion on their chest. It's an interesting indicator of where America's passion and heart is leaning."

Maniatis said that the website's sales accurately predicted the 2004 and 2008 presidential races -- as well as the primaries in the latter.

If the barometer is still working, then the tea parties are all the rage now.

Popular conservative shops like Right Wing Stuff have hundreds of designs tailored to the tea parties, ranging from the health-care era, "Stupid is as Stupak Does," to the everlasting "Don't Tread on Me."

Run by a former Silicon Valley techie who now works out of the sun room in his California home, Right Wing Stuff offers more than 900 designs that mock "ObaMao" and hail leaders like Sarah Palin and Sen. John McCain (R-Ariz.).

What's popular depends on the news so site owner Jim Gamble spends a lot of time watching cable news channels for a political gaffe or timely topic.

"My mind works in sort of a bumper sticker mentality," Gamble said. "We can have something up within an hour."

Gamble said he used to throw every design online "to see what would stick," but that he's more selective these days. After drawing his own stuff for a few years, he hired a graphic designer, conservative political cartoonist Linda Eddy, in 2005.

The two came up with a bestseller in favor of the Arizona immigration law. Governor Jan Brewer's face is imposed on Rosie the Riveter and the shirt reads, "Arizona: Doing the Job the Feds Won't Do."

Eddy, who also has a separate Cafe Press shop , said her sales quadrupled in May because of that shirt. Many conservatives bought it for a May 29 rally in Phoenix.

"It's absolutely snowballing at this point," Eddy said.

The shirts can be big business: Melanie Morgan , a talk show host who create a Sarah Palin T-shirt during the 2008 presidential campaign, said she made $25,000 from it. The election may be over, but sales still roll in from that item.

There are liberal tees too, of course, like those that blast the Arizona law and play on Vice President Joe Biden's health care gaffe, hailing the Democratic victory "a big f---ing deal."

The iconic silhouettes of Obama's face that were so popular during the election still sell, too.

Simple designs like that one work the best for these websites, according to Jason Bostic. He runs the conservative American Elephant store on Zazzle.

"People look at these images in a small 150-pixel thumbnail. When you've got fine lines and a lot of text, it gets blurry," Bostic said.

The North Carolinian worked in a print shop designing T-shirts in high school, but it wasn't until his mortgage business went under during the 2008 market collapse that he turned to selling shirts full time.

Now he's making more money than he was selling mortgages without the overhead costs of running an office.

"The beauty of print-on-demand is that I can design something and put it up. If it doesn't sell, I'm only out the time of the design," he said.

But the low barrier to entering the T-shirt market can also present a challenge. The designers have to move quickly to outpace their competition, and they live in constant fear of missing a popular design.

"If a smaller blog mentions something and then a bigger one mentions it, then it's really going to pick up steam. But if you wait until it gets to the bigger blog, it's usually too late," Bostic said.

Like most sellers on these sites, these designers cater solely to their end of the political spectrum.

Gamble owns the Left Wing Stuff web address, which he redirects to his Right Wing Stuff store, and has given thought to adding liberal goods.

But be believes that's not how this marketplace works. A tea partyer is unlikely to drop $28 for a shirt on a site that offers pro-Obama merchandise.

"The people that buy our stuff are very principled," Gamble said.

Ambreen Ali writes for Congress.org.

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