Or when you wake up, on a crisp, clear autumn day, a Saturday, when the leaves are changing color. You hop on your bike, with no destination in mind. You can ride 50 miles, or 150 miles. Either way it's bound to be a great day.
It's the feeling you used to have back in elementary school on the first day of summer vacation. You can do whatever you want to do. Your imagination is the limit.
That's how I feel right now.