Back when I owned a small (21 foot) sailboat I'd go out alone - the ultimate escape from the concrete jungle. Someone ashore always knew where I was and when I could be expected back though.

When flying either RC or CL, I always take my best flying buddy - my 15 year old son. I can't recommend flying alone. For one thing, it's just not as enjoyable and secondly, the risk of serious injury is too much. I've only got one very small scar from a half-A engine back when I was in high school. Goldberg half-A Skylane. I reached over the prop to turn on the receiver switch and nicked the fleshy underside of my forearm. I've always used the utmost care since then but all it takes is an instant of inattentiveness to mess up your day.