Prominence requires finding a mountain's "key saddle" -- the pass that connects the mountain to higher ground. This may be an unremarkable point hundreds of miles away, often with several candidates whose elevations differ by only a few meters. Oilslick was designed with the goal of helping locate these points and intuit their significance. The color banding helps visualize the saddle 'pinch points' with relative ease, and the high-contrast color ramp enables the necessary fine discernment in elevation values, even for points located far apart.
You can peruse my (very preliminary, mostly mothballed) prominence work here [http://mrgris.com:10011/summits/?max=2500]
What I didn't expect was that the end result would be so aesthetically pleasing, almost dazzling. I love how it brings out subtle geological features and big-picture structure and relationships between landforms that don't show through in traditional topographic maps.
I share some of the criticisms I've read here. The zig-zag points on the ramp where the brightness must double back create contrast 'dead zones' where it's hard to interpret what's going on. Sea level areas are very dark and the actual coastline is hard to discern. Partly this is from practical limitations of not using a coastline mask in addition to the raw elevation dataset -- I don't actually know whether a point is land or water. But nevertheless there is interesting detail in these coastal areas that oilslick currently doesn't do justice to.
Overall it's been great to read the reactions here and see some people's perception of our world getting warped for the better.