It works really well. I basically copied the Xebra owner's installation exactly, right down to the style of handle (which falls nicely to hand... ergonomic and everything).
I've already "dinged" the bell out of anger at a girl in an SUV who pulled out in front of me while driving along (not because she couldn't hear me, but because she was demonstrating a general lack of driving skill and/or manners).
Haven't actually rung it - out of necessity - for a pedestrian yet.
Photos! (Video to follow! Maybe even sometime in 2009!)
Here's the bell, positioned up close to the hood/bumper gap for best ... alerting. The OEM horn is installed pretty much in the same position on the other side.
Handle is a piece of aluminum tube, with hole drilled in it. The cable goes in the hole, then I tightened a nut & bolt on the end to give me something to pull against.
Ding ding! "Hey kids! It's the ice cream truck! No, no. It's that killer electric car again."
Here's the Xebra video again. My setup is nearly the same. Just picture the ForkenSwift instead of a 3 wheeled, 4 door egg: