I love bicycling, but it is tricky with kids 5-10: too old for bike seats, too young for tandems (which are also expensive). For $90 the Pathfinder Bike Trailer provides a way to bring the kids along, give them exercise, and be able to talk with them during the trip. Because I have three kids, we hook a Burley Trailer to the Pathfinder so someone can rest on long trips. Alternately the older one rides on a tandem with me or my wife. This device turns bicycling into a group activity and has instilled a lifetime love of bicycling in my kids.
A cool tool is anything useful that is superior to comparable items. If you think this tool is inferior suggest a better one. You are welcome to insult a tool, but comments containing insults to individual people will be deleted. Corrections of fact are always welcomed, if stated politely. Recommendations of better tools are dearly wanted and may be elevated to the front page.