|Documentation file and examples|
Documentation, howto and example code
|How eBay Uses Metadata to Enhance Its Web Services|
Article on eBay's self-documenting XML schemas. Note that it is from an earlier version of the eBay API, but the ideas are still interesting.
|Latitude Longitude Functions|
Page contains sample code for querying the geocoder.us methods for great circle distance and zip code distance.
FeedbackRoad User Api Specification
|Twilio Hello World Tutorial|
In this getting started with Twilio tutorial, you'll build a simple application that reads you back "Hello World" when you call a phone number. Uses plain old XML.