Al Doyle's latest "Silver 101" column at CoinWeek is titled "Don't Lose These Little Silver Coins," covering some of the tiny silver coins that circulated in Europe as late as the mid-20th century. He notes that many of these coins were less than half the size of a U.S. dime! If you're searching for an "overlooked" area of coin collecting, this may fit the bill!
Since we have no minimum levels for buying silver at Gainesville Coins, we sometimes see itty bitty silver ourselves. One example is this Swiss 1/2 Franc silver coin, minted between 1875 and 1967:
We usually have many different silver world coins under a half-ounce, and they make great gifts for introducing someone to coin collecting. You can search any category and sort by "Lowest Price" to find all sorts of hidden treasures.