Spend an evening cheering for today’s college baseball stars, many of which will be tomorrow’s major leaguers. One in seven MLB players played in the Cape Cod Baseball League at some point in their career, making it one of the best amateur summer leagues in the country (alumni include Mike Yowell, Jason Varitek, Tod Helton and Carlos Pena). Best part: Admission is free at the 10 beautiful town ballparks.