I’m blogging from Startup Weekend Boulder 3, but cross-posting on my own site.

One of the most important things one can learn from building a startup is that having a good idea, but it’s not enough. Other people might’ve already done something with your good idea — and if you can’t do it any better, you might want to move on to the next idea.

That’s what we figured out in the group dedicated to solving our language problem. Although it’s true that we had a good idea — basically, matching people to other foreign language learners at their level and providing a web space to video chat and connect on forums — we have discovered that the service is available elsewhere, and we didn’t think that we could compete.

We’re now developing another idea, and here’s what we’ve come up with so far:

• Creating a database of information that can be easily accessed when you lose your credit/debit cards and need to cancel them
• Making reservations at restaurants via Twitter
• Gathering a database of clothing sizes over different brands so that one can more easily order clothing online (i.e., if I’m an 8 in Banana Republic, what size am I in other brands?)