What is the value of a 1908 Irish coin?

Assuming you are referring to a U.S. one cent coin, 1928 cents are not rare. Check under the date to see if there's a mint mark letter. As of 02/2009 approximate retail values are:

No mint mark - very worn, 10¢; moderately worn, 50¢; almost no wear, $1.50

"D" mint mark - 20¢ / $1.00 / $5.00

"S" mint mark - 45¢ / $2.00 / $7.00