We've been talking about using a t-shirt as a means to disseminate instructional diagrams of DIY citizen science tools related to our new initiative PublicLaboratory.org.
Imagine a t-shirt which lists all the materials you need to fly a balloon mapping rig, like in the illustrated guide: http://grassrootsmapping.org/guide/
This idea for distributing the 'source code' of a DIY science tool for investigating your environmental health could be very powerful.