Scale Conversions. Converts map scales given in ratios or representative fractions into word statements. Only works in one direction. Courtesy the University of Texas, Bureau of Economic Geology(?) via The Map Room.

The Marteau Early 18th-Century Currency Converter.  Every wonder how many pennies in a groat? Need to convert your guilders into piasters? Want to know the wages of an English barrister in 1710?

"How to become an Ascended Master of Google-fu..." Nick Pelling's very helpful article on how to make your Google searches more effective.

Courtesy Tiporama, the Image Size Calculator converts from pixels to inches and back again.

"Caring for your [Antique Map] Collection", via the International Map Collectors' Society (IMCoS).

"Rare Book Photography: An Introduction" by Bryn Savage and courtesy Yale University.