Switzerland is famous for a few key goods: watches, chocolate, cheese, and Swiss Army knives.
Watches - Switzerland is the watch-making capital of the world, and "Swiss Made" on a watch face has long been a mark of quality. While the French-speaking regions of Switzerland are usually associated with Swiss watchmakers (like Rolex, Omega, and Patek Philippe), some fine watches are made in the Swiss-German-speaking region, such as IWC in Schaffhausen. Every large town will have quite a few horologers and jewelers with a vast selection of fancy watches displayed their windows, ranging from the fashionable Swatch for CHF60 to the handmade chronometer with the huge price tag. For fun, try to spot the most expensive of these mechanical creations and the ones with the most "bedazzle!!".
Chocolate - Switzerland may always have a rivalry with Belgium for the world's best chocolate, but there's no doubting that the Swiss variety is amazingly good. Switzerland is also home to the huge Nestlé food company. If you have a fine palate (and a fat wallet) - you can find two of the finest Swiss chocolatiers in Zurich: Teuscher (try the champagne truffles) and Sprüngli. For the rest of us, even the generic grocery store brand chocolates in Switzerland still blow away the Hershey bars found elsewhere. For a good value, try the "Frey" brand chocolates sold at Migros. If you want to try some real good and exclusive swiss chocolate, go for the Pamaco chocolates, derived from the noble Criollo beans and accomplished through the original, complex process of refinement that requires 72h (quite expensive though, a bar of 125g costs about CHF8). For Lindt fans, it is possible to get them as low as half the supermarket price by going to the Lindt factory store in Kilchberg (near Zurich)