From OpenStreetMap Wiki
TileSweep is a tile server with prerendering.
- Selection based prerendering capability, tiles are stored in a single file.
- Can be built and run without Mapnik if you have an existing tile database.
- Single executable with an embedded HTTP server
- Scales with CPU cores
- Serves both 256x256 and 512x512 tiles
- Can prerender and serve tiles simultaneously
Project page: https://github.com/seemk/TileSweep