Nearly 200 geeks -- divided into 15 teams --  gathered at Microsoft's Redmond campus this weekend to take part in Startup Weekend. The 54-hour coding marathon brought together a wide array of entrepreneurial types, some of whom had more polished ideas than others.  But everyone appeared to be having fun, watching and learning as new business concepts sprouted in hours.

"The last three days have been kind of grueling, especially when you have to get something online," said Junaid Ahmed, a Microsoft employee who led the AzureAlert team.

Mei Lu of Backseat Casting -- a service that allows people to suggest actors for movies -- put in some long hours as she tried to get the service off the ground.

"If I am rambling, it is because I only had two and half hours of sleep last night," said Lu during her 10-minute presentation.

Ken Smith -- who participated in the team MapMyDate -- summarized just how tough it is to go from idea to product to formal presentation in 54 hours. In a Tweet, Smith wrote:  "Our presentation: roughly 45% smoke, 30% mirrors, 25% reality."

The best named startup of the day? Kevin Lenaway's "Where's the Toilet." The Windows Mobile application is a new travel guide that incorporates a digital phrase book, an application that won applause from the audience.

"This isn't going to be a billion dollar business," said Lenaway. But he said it could be a nice, niche product.

In fact, that's probably the case with most of the projects invented at Startup Weekend. But some of the concepts are already on their way to sales -- and profits.

Roy Leban scored a big sale during the 10-minute presentation when he started a bidding war for the first sale on his site FriendMosaic, a photo collage that uses images from Twitter. BizSpark -- a sponsor of the event -- stepped forward and purchased T-shirts based on the Twitter mosaics for everyone in the room. (About a $2,500 sale).

Not counting the time invested by the team, that means FriendMosaic is already profitable.

"I would have been happy with one $19 sale," said Leban.

Bitter presents at Startup Weekend.

FriendMosaic puts the finishing touches on their product before presenting at Startup Weekend.

Kevin Lenaway, left, and Kunal Hahajan of Where's the Toilet.

Brandon Watson walks though a demo of MapMyDate

Whiteboards at Startup Weekend.

Microsoft's Brian Gorbett, left, looks over Ryan Kyle's Common Ground

Chime Back showed up in matching T-shirts.

GoForBooks' developers listen to presentations.

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