My bike did come with a bell but I removed it cos it was gay. (TJ, take note 
).
When approaching walkers I do tend to slow and find the noisiest piece of the approaching trail, (leaves, puddles etc) and ride over it. It usually does the trick. If they step to the side, keep hold of their dogs, gather the kids then I'm polite and thank them. If they don't hear then I slow right down so I don't scare the sh*t out of them. I realise this can be a bit of a bind if you're training or whatever but bikers don't own the trails, we need to share. If walkers annoy you, go somewhere with less walkers.
My personal favourite though was when I was tearing around the Necropolis in Glasgow, a dog walker approaching from THE OTHER DIRECTION wasn't paying attention and I gave him a bit of a fright. He launched into a four letter tirade about how this was a graveyard and I shouldn't be here. Meanwhile his dog's pissing on a headstone. You can't win em all.
