The Mobile Web Server, a concept previously available as the Raccoon project (http://sf.net/projects/raccoon/), has just been released in productised form.
Now anyone can easily host their own mobile website on their phone. The ready-to-use web applications in the release package include a blog, a guestbook, a gallery, remote viewing of contacts and calendar information and more. Advanced users can easily write their own web applications in Python.
Use it, tune it, or develop it - it's ready for trial.