Do you mountain bike alone?

[sundial]

Go out prepared for the worst.

Sage advice! I do wear my Road ID, carry my cell, and the Spot.

[bounceswoosh]

Pretty much what TahoeDirtGirl said, but --

I do ride alone, and in fact have come to enjoy it. I like being able to go my own pace and do my own thing. That being said, when I'm alone, I go to trails that I know well and that tend to be pretty busy.

I haven't really ever worried about creepy people; since I try to go to places where there's a lot of traffic, I would expect that to be a deterrent. Or if someone did actually approach me, I would expect another person to encounter us shortly.

I bring just about every tool I can fit in my Camelbak; if I can't fix it, I figure someone else will. This also helps my bike karma, since I can let others on the trail use my stuff when they get stuck =)

I also always bring my cell phone; it may or may not work out there, but it's worth a shot.

Even if you don't live with people who would notice your absence, I would imagine you could set something up with a co-worker or friend -- tell them where you'll be and tell them you'll call them by some set time.