Explore the middle of the island of the Dominican Republic. I got to know a guy doing gold panning. Was really great !! Going all day to the river panning for gold and REALLY found a lot of gold you can keep. BIG fun and a great experience.
This article has a great list of outfits for adventure activities like kayaking and whitewater rafting in the Dominican, especially Jarabacoa, although the outfits in the links can set you up for other places too. there are also links to other good articles on other areas and activities and the Dominican. I also just found a local guide through one of them. www.suite101.com/content/raft-kayak-in-dominican-republic-a38874