Do small code presentations
Every time a team or a single developer releases a piece of code for internal consumption, an overall presentation is a good thing to have.
That way you get the chance to
- avoid going through every desk and explain intent or usage
- state reasoning behind implementation
- give an example on how it should be used
- show how it can be extended
The presentation should be complimentary to comments (e.g. Javadocs) and unit tests.