As INTPs, I think we're often in an interesting predicament where we yearn for change and adventure in our lives (Ne I suppose?) but we're also generally highly reluctant to give into these impulses if they don't match our logical thought processes of what we really should be doing (or really anything we can rationalize-hence video games all day is included).
Now and then though, we just say screw it and jump into something we thought up or were presented on the spot, and I think it would be fun to share these times. Most fun, most stupid, biggest impact on your life, etc., etc.-whatever you think would be interesting to share.
I don't have anything that cool, young and lazy as I am, but I'd say something recent that was pretty big was my random determination to run like 5 miles in terrible pouring rain. The longest I'd ever ran before was like 3 miles, and that practically killed me, but I just went out and did this, and not for any logical reason. That one run made me start running regularly and now I'm trying out for the school cross country team.