Google Maps dominates the online mapping scene, but there's also a vibrant community dedicated to producing open source maps. Smart phone software developer BigTinCan is tapping into that market with a suite of mobile mapping products.
While the BigTinCan mapping service lets you contribute general points of interest information to the OpenStreetMap project, perhaps the most interesting addition is its TidyMyStreet application, which lets residents identify problems in their area such as potholes and graffiti that need to be repaired by local councils and other authorities.
Along with the web version, BigTinCan has also released mobile mapping applications for Android and BlackBerry, and is promising iPhone and Windows Mobile versions "soon". If you give either mobile version a spin, give us the good oil in the comments.