I just saw a video by the noted RC blogger "RCSchim" that demonstrates a cool device called the Marco Polo. It looks quite promising, and could be a very inexpensive (~$200) insurance policy for the more adventurous among us. As for me, I'm undecided, as my flights tend to go mostly straight up and back down. But if you're operating over dense brush, trees, or other difficult terrain, it could be a very good investment. http://eurekaproducts.com/rc-model-tracking-and-recovery/ Here's RCSchim's video demo.
I bought one of these and did some field testing in a 400+ acre graveyard where we go for walks. I told my girlfriend to hide it anywhere while I waited. The terrain is varied with deep canyons and heavily wooded areas. I was impressed. After a few tests I let her 9 year old use it to find the beacon. It was that easy. If we were below the beacon or in a deep canyon when it was above us we would get no signal. But once up on higher elevation it picked the signal right up if we were in the area. One test it was about a mile away. If I remember correctly I got signal about a half a mile away and it pointed right towards the beacon. Well worth the money.