The current svn version allows recording of demos. So let's collect some speed runs :)
(Unfortunately the speed runs can only be replayed with the same version of supertux it was recorded with...)
MatzeB (svn version from 2.Mai)
First note that Demos are only available in the development version! If you have compiled an svn version yourself, then you can record a demo of level25 like this for example (started from source dir):
./supertux --record-demo mydemo.demo data/levels/world1/level25.stl
supertux.exe --record-demo mydemo.demo data/levels/world1/level25.stl
You can playback a demo like this:
./supertux --play-demo mydemo.demo data/levels/world1/level25.stl
supertux.exe --play-demo mydemo.demo data/levels/world1/level25.stl