Have you ever printed a map? Clicked a hundred times on "Export" button on osm.org? Installed mapnik or maperitive and spent days configuring a database and customizing a style? Did you wish for a simple web service that lets you select a bounding box and produces a hi-dpi raster or vector image? Well, there is one now. It is called Get Veloroad, for a style it was created for.
On the side panel you choose paper format and margins, add a GPX trace if needed, select style ("veloroad" and "osm.org" are available), image format, and press "Submit". If the server is not overloaded, you'll get your image in a minute, in glorious 300 dpi. SVG files are postprocessed, so you can easily move labels as a whole, instead of separate letters (the most annoying trait of mapnik-generated maps).
Alas, my server cannot fit all the planet, so there are only Baltic countries and parts of Russia and Finland. Everything is open-sourced though, so I hope soon we'll see a worldwide service for producing high-resolution images.