As Fly operatives head to DC to keep an eye on Silicon Valley’s vain and connected, they are noticing that the Obama presidency is already having a positive effect on the economy. To wit:

• Washington, DC bars have gotten the official green light to serve alcohol until 5 a.m. for four days, which should contribute to the city’s tax revenues. San Jose tried this when it was a capital city in 1849 for the Legislature of a Thousand Drinks, said to be one of the most productive legislatures in California history. More recently, the city flirted with the idea of extended alcohol-free closings for downtown bars, but the idea seems to have been forgotten.

• AIrlines and transportation agencies hammered by high fuel prices in 2008 got an unexpected boom, with sold out flights to the East Coast during the normally slow January season.

• The shrinking necktie department at the Stanford Shopping Center’s Neiman Marcus, where $200 ties are sold to Silicon Valley execs who these days walk around with unbuttoned collars or, in the case of Steve Jobs, turtlenecks, experienced a weekend run on any silk nooses with patriotic colors in them. Sales personnel grew experienced at identifying the DC-bound. “Heading to the inauguration?” they’d ask, and the answer was invariably yes. “One right after another,” a saleswoman commented.

• Room rates at the Motel 6 Washington DC were running at $600 a night. You can leave the light off…

• The souvenir industry is experiencing a boom in Obama tsotchkes, from bobbleheads to coloring books. Here are a few of our favorites, photographed at Dulles Airport: