Hmmm I don't have all the stamps, I'm not sure where to look them up. But I have 24 experience and the ones I have are:
First time using a net ticket
First to arrive to a user's namahousou
Continued premium membership
Viewed a video on a mobile device
Linking PC and mobile
Used an application
Commented on a new video
Frequent visitor
Downloaded Niconama Alert
Somewhat frequent visitor
Mylisted a new video