MICHAEL J. Whelihan is focused on his money. The local numismatist -- paper money collector -- displays his prized bank notes in plastic sleeves, and is in constant search for unusual additions to his over 500-piece collection.

"To me it's beautiful, artistic and just plain interesting. Being a numistmatic is like being a detective and a good shopper," said Whelihan. "I work with 35 different dealers and collectors around the world."

His interest in collecting began in 1970 after traveling to the Sinai Desert, Vietnam, Germany and Panama with the army. He saved a few notes and coins, but didn't begin collecting seriously until 1993.

Three Japanese bills saved by his father during World War II are one of his most prized items.

"I am an amateur history and geography nut," he said. "I want to collector two or three banknotes from all 297 countries that ever existed. The hardest ones to find are those from countries which lasted only two or three years."

In the meantime, Whelihan has broken his three-note-per-country rule with several pieces from the U.S., Israel and Ireland -- all special places to the collector. His ancestors are Irish and he was station in Israel for over a year.

He writes for the trade publication "Lansa," and has "discovered" several notes unknown to its catalogue. The unsigned 20-colon banknote from Jan. 1, 1906 was entered in the books this year after he came across it while trading here.

Although there might be other 20-colon bills floating around, his is the first unsigned remainder known to the book.

A note can be discovered as issued notes, unsigned remainders (notes that have no signature), overprints (reprinted notes) or specimens.

Before money goes to press, proofs are made to show the color scheme. Then a specimen, or final proof, is made. Specimens are worth more because only a few of them are made.

"If you have a specimen you really have a valuable note, no matter how old or what condition it is in."

THE value of a banknote depends on its age, series, issue, how many were printed and whether it has any mistakes. Usually the older it is, the more it is worth.

"Having [the collction] is like money in the bank," said Whelihan. "I try to get the first issue in the best condition at the highest grade and highest denomination."

Additionally, he recently submitted a 100-peso bill from Costa Rica that was not known to exist as an overprint. He discovered five Polish notes that were unknown as specimens.

AS much as he's interested in the value of his collection, he is fascinated by the details and artistry on the notes. For example, while French money is dull, French - colonial money is bright and beautiful.

Some countries share the same vignettes or pictures on their bank notes. Peru had the same picture on the 10-sol bill from the 1800's as Costa Rica's 20 Colon bill from 1900-1901.

And he said many South American countries used a portrait of a dog on their money - though he doesn't know why.

BECAUSE former Costa Rican President and Nobel Peace Prize laureate Oscar Arias was so popular, banknotes with his signature are worth saving. The most common collectibles are the P-239b, 5 colon bill, May 8, 1972, and the P-236a, 20 Colon bill, July 10, 1972.

Whelihan also noted that some counterfiet notes are worth more than originals. He has a British pound that was one of many copied by Germans to hurt Britain's economy during WWII.