This Pipe allows you to geocode addresses listed in a Google Spreadsheet document.
The spreadsheet has only 2 columns: "name" for the item title and "address" for the address to geocode. To geocode all rows, just publish the Google Spreadsheet as feed (Atom or RSS) and tell the Pipe the feed url. See an example here: http://spanring.eu/blog/2008/01/09/mapping-google-spreadsheets/
Pipe Web Address: http://pipes.yahoo.com/spanaut/geocodegooglespreadsheets