our family has taken on a new hobby....it's letterboxing. I first heard about it in Family Fun magazine...
it's similar to geo-cacheing but you don't use a gps unit. you look up the site at letterboxing.org and choose the location you want (there are letterboxes all over the U.S.). Then you choose a specific "treasure hunt" in a more specific area, and then print out directions.
We did one last weekend at the lake. It took us on a trail, and told us things like "go down 30 steps and then 22 paces forward," and then look for the box hidden somewhere, like, "in the hollow stump of the tree on your left," or something similar. On this hunt, there were 4 boxes; we found 3. Inside each box there is a rubber stamp and pad to put in your own log (we started a small notebook just for this new pasttime) and then you can leave you own stamp in their log as well. We took along a stamp to represent our family, and it was amazing how many other people had found these "treasures" and stamped the log...from all over the U.S.
All of our kids LOVED doing it, and have asked several times when we're doing another one. So, whereever you are, if you're bored sometime, look up the site and try it out for yourself!! It's fun, and free!