In the early 16th century, Frederick the Wise, the Elector of Saxony, possessed 19,000 holy relics. These included a thorn from the Crown of Thorns, a crumb from the Last Supper, a twig from the Burning Bush and 204 bits of the children massacred by King Herod. Anyone who viewed these on the correct day of the year and made the necessary gitfs of money would be spared two million years in Purgatory. One can see why one of Frederick's subjects, Martin Luther, began to have doubts on the subject!
(Source: B. Gascoigne; "The Christians")