John F. Kennedy famously called it a city with "southern efficiency and northern charm." Others say it's "Hollywood for ugly people." A century ago, apparently, it was known (oddly) as the City of Magnificent Distances.

Yes, I'm talking about our nation's capital: Washington, D.C.

D.C. isn't exactly known as a leading hotbed of innovation and entrepreneurialism. More like government grey and bureaucracy–a place where former student-council members find out they're not really all that special.

But the truth is, there's actually lot of innovation here. LivingSocial is headquartered barely a mile from the White House. AOL once seemed destined to rule the world from an office park a few miles in Virginia. That said, it was surprising to find out that a Tech Meetup here this week ranked No. 1 in the world in terms of attendance and RSVPs (on Meetup.com, if that's not otherwise clear).

More than 1,100 people signed up for "Hacks, Code, and Creative" at D.C. Tech, to hear a dozen entrepreneurs and innovators pitch their ventures, ideas, and experiences. As a typical Washington type who is never quite sure when work ends and life begins, I combined my searches for hot stories and cool women by bringing a date.

"OMG you took a girl on a date to D.C. Tech Meetup? If I read that right that's amazing," organizer Peter Corbett, CEO of iStrategyLabs, emailed me later when I asked him to double-check attendance numbers.

"It was the biggest Tech Meetup in the world," he continued. "There's one qualifier. NY Tech Meetup did an emergency rally to stop SOPA where 1,600 people attended a protest in front of Senator Shumer's office. In my mind that's a different kind of meetup than what we did."

The crowd can be kind of crazy at these events (in a good way), and the rules are simple: Each formal presentation gets five minutes, max. The presentations are followed by an open-mic session where anyone in the crowd can announce a Twitter-length summary of what they're working on. The line for open-mic at the end stretched nearly out the door.

New York, Tel Aviv, and London normally top the Tech Meetup list in terms of RSVPs and attendance. Washingtonians are notoriously bad at estimating crowd sizes, but I think Corbett's probably on the mark when he estimates that about 700 people were there at the peak.

So, what are they working on in Washington? Between what I've seen and some of Corbett's choices, here are a handful of D.C. Tech innovators and entrepreneurs:

  • Opower:  Customer engagement platform for the utility industry that "reinvents the way utilities interact with customers--from the quality of the information provided to the way it's presented and delivered."
  • ExFed: Startup (now in Beta) connecting former government workers with contractors who need to hire former Feds.
  • Hungry Academy: LivingSocial needed engineers, so they launched this pay-as-you-train and get-a-job program.
  • Surc: Converts your iPhone 4/4s into a universal remote.
  • MapBox: GIS mapmaking solution. Foursquare just implemented it to replace Google Maps.
  • Doodle or Die: Addictive social game created by two guys in a D.C. bar. Check it out only if you have a free afternoon.
  • GE Social Fridge: Bizarre but compelling SXSW project. A vintage 1939 refridgerator hacked to pop open after 10 people check in on Foursquare, and share its stash of ice cold beer.
  • Relay Foods: Virginia-based Internet grocery delivery company, trying to solve the "last mile" problem so they can flourish in sparsely populated areas.