I was just answering a post in another thread, and it brought to mind a quirky situation that you guys might get a kick out of.
We've been playtesting a game over the past several months that uses a fair number of money counters. By "fair number", I mean that each player typically has up to two hundred "gold".
I searched and searched for an easy way to represent the gold. I'm not a big fan of the little cardboard counters (ala Illuminati) for testing. They're a pain to make and don't hold up very well. I looked at chips, but the cost of poker chips was prohibitive, and I really didn't want to make stickers and stick them on.
So...I ended up using real coins. I went to the bank and got a couple rolls of pennies, nickels, dimes and quarters. It works like a charm! The coins hold up to rugged handling, there's no learning curve as to what the money represents, and playtesters are particularly careful not to lose them.
It also gives the table an exciting feel to it, as onlookers see piles of coins scattered here and there.
Gogolski, those flip-caps are a great idea - but from your Google link, it looks like they cost more than a penny a piece. It's cheaper to use real pennies!