Update 2011: Some of my photos from this project appear in the book This is Service Design Thinking.
As part of research into homelessness for the CHI 2008 Student Design Competition, I distributed probes among homeless in Stockholm. In what can be said to be a DUH! result, the response rate was low, despite a positive attitude and expressed willingness among the participants. In the paper we wrote as part of the competition entry, we suggested a type of service based on basic needs being fulfilled before requiring any action on the part of the homeless person.
I designed and carried out the study myself.