This DT&I (Detroit Toledo and Ironton) work crane and boom car set by K-Line caught my eye, it's the first set of this type I've acquired in O gauge.
These road name labeled versions are an interesting staple of model railroading that were rare in real life. Actual railroad lines didn't want work cars cleaning up derailments, etc. to have their names on the side (they didn't want to be associated with train disasters) so these actually came in either plain colors or if marked were marked with the manufacturer's name. The 'work caboose' was also rare, these were usually just plain flat cars.