The lovely two-tone bell which came with my Raleigh DL-1 recently met its end. It went from being a two-tone to a zero-tone bell, most likely as a result of my neglecting to rotate the bell before flipping the bike over when doing bike, such as re-gearing in February. I like two-tone bells, their sound seems much more polite than the standard ‘ping’ bell supplied with most UK bikes and is generally received more positively.
Thankfully, my recent visit to Chorlton’s Big Green Festival provided me with an opportunity to replace it with a Velo Orange Temple Brass Bell courtesy of Practical Cycles. Whilst the new bell is only a single-tone, it has a pleasant sound which doesn’t feel as ‘rude’ as a ping bell. It’s pretty classy looking to boot.
Chester Cycling (and other stuff) 
The brass has a really delightful, sonorous tone, I think. I have the lever strike version on my tourer/commuter, and I really like it.
I’m quite happy. My first Velo Orange product as well. Wouldn’t mind trying one of their saddles one day.
My bike bell was a kind gift, though I think its bonus is that it looks pretty rather than sounds pretty: http://www.octopusshop.com/catalog/product/view/id/2006/s/spring-bell-bdcf49ae0010/category/10/ . Accidentally scratched the hell out of it when I flipped my bike upside down. Never mind! People still move out of my way when I ring it 🙂
Nice. Have you checked out Ridelow? They do all sorts of interesting looking bike stuff.