Tripit, one of the companies that launched at TechCrunch40 is an extremely useful application for frequent travelers.

It’s dead simple to use and it keeps you organized - all you have to do is forward confirmation emails to them when you purchase airline tickets, hotel reservations, car rentals, etc. Tripit pulls the relevant information out of the emails and builds an organized itinerary for you. You can send emails in any order, for multiple trips, whatever. It just figures everything out and organizes it.

The best part is you don’t even need to register to start using it. Just take an email and forward it to plans@tripit.com. Within seconds you’ll get a confirmation email back and you go from there. If it doesn’t recognize the email format from the seventy travel companies they currently support (orbitz, united airlines, marriott, etc.), you can add the information in directly on the website.

Today at the Web 2.0 Summit CEO Greg Brockway is launching a new feature that makes the service even more useful, particularly on a mobile device (what you have with you when you travel). You email a basic command to the service and it responds with relevant information. “Get Flight Today” will return today’s flight information, for example. Or just “Get Trip” to get full details of your most current trip. Or just email “Help” to get a list of possible commands and modifiers.

San Francisco-based TripIt has raised $1 million from O’Reilly AlphaTech Ventures