The Story of Bilal
This is a heavily disputed narration amongst the muhaddithin. You have Hafiz Ibn Hajr, Adh-Dhahabi, Mulla Ali al-Qari, Ibn al-Arraq etc all classifying it as a fabrication, while Allamah Subki etc classifed it as hasan! I go with the first, but you will find many taking Allamah Subki's view. As Ahmed al-Ghumari mentioned "Ibn Hajr will never classify a narration as a fabrication unless its spuriousness is clear like the sun at midday". (al-Mughir)