Over at MIX09, Dan Harrelson talked about design prototyping and touched upon many interesting points. The ideas he raises include prototypes as being: dynamic, disposable, responsive, focused, explorative and fast. Perhaps these are not completely novel thoughts, but they area a very nice summery and definitely refresh how prototyping differs from designing wireframes. Dan also states that the nature of prototypes is in line with agile development which values less documentation over richer conversations. Further, Dan also goes over two quite popular prototyping techniques: paper prototyping and digital prototyping (with Axure).