Thanks to Jan Meisels Allen, recent recipient of the National Genealogical Society’s 2013 President’ Citation for her work in preserving access to genealogical records for alerting us to the National Archives of Ireland’s news.  Jan wrote:

"The National Archives of Ireland added to their genealogical collection by
releasing a new database: Calendars of Wills and Administrations 1858-1920 
- an index of wills and administration in Ireland. The database can
be searched by county, the name of the deceased person, the names of
executors and the names of beneficiaries.  Access to the database is free.

You may access these records by going to:
http://www.willcalendars.nationalarchives.ie/search/cwa/

A typical entry lists the name, address and occupation of the deceased, 
along with the date of death, the date and place of probate, the names and a
ddresses of the executors, beneficiaries of the will (and their relationship 
to the deceased) and the financial size of the estate.  I tried the name 
Cohen and several "hits" returned.

These calendars cover all of Ireland up to 1917. Since 1918, wills and
probate from the six counties of Northern Ireland are searchable on the
Public Record Office of Northern Ireland (PRONI) go to:
http://www.proni.gov.uk/"