The Treasury not only issues a wide variety of debt in different maturities--ranging from four-week bills to 30-year bonds--but it also offers TIPS, or Treasury Inflation-Protected Securities, whose returns are linked to the inflation rate. If you worry that inflation is returning, invest in iShares TIPS Bond (TIP, $114), an ETF that holds TIPS with maturities averaging eight years. When stocks rise sharply, it usually indicates that optimistic businesses and consumers are doing more borrowing and anticipating more inflation, which in turn means higher interest rates.