There's a nice paved greenway about 1/2 mile from my house that I use as a nice warmup before my ride. When the weather's nice, there's always peds walking on the greenway. I keep a slower pace on the greenway (< 15 mph) but when I come up on a ped I'm always torn on what to do. Of course, they are usually walking 2 of 3 wide and taking up the entire lane, so just riding past usually isn't an option. Then again, if I yell out "on your left" so they know I'm going to pass them on their left, most of the time I'll get a dirty look. Maybe I should try the waterbottle trick and just squirt them as I approach.