I have noticed that when writing specs you waste a lot of time on things, that later, when you write your app are negligible, and you forget some important stuff.
I have found it to be faster (for me) to write a proof-of-concept application (no good error handlers and security stuff, minor gliches in the style etc) and use that as a spec for those who join me.
Still, I feel I am wasting time in this method too, any good ideas on how this should be done?
Seems like you're arguing in favor of Agile Development
Using this iterative process, our team is able to "rank" features on a scale of importance and then weigh the release date with the features they want (in a nutshell)
An interesting approach to a spec are "tests". For high-level stuff you write acceptance test using tools like Fitnesse and for low-level stuff you write unit-test.
Once a dev is done with coding, running the test suite verifies that all the spec is really working.
This approach expects that the person who writes the spec is capable of expressing himself in terms of tests. This is usually not true and therefore this approach is more like an utopia. But still, you might try it.