Here are some things I've worked on that are related to public transport.

SGTransport: I (and a few friends) run a public transport-oriented Facebook page and Flickr account.

/misc/transportfiles contains transport-related files, including foldable bus paper templates and a guide on how to read printed bus tickets.

A Guide to Public Transport in Singapore was written for people (like tourists) who are completely new to Singapore's transport system.

Alstom C751A openBVE add-on, a fairly realistic representation of the 6-car North East Line trains.