Market tip

Market tip

Just as consumers can’t seem to get enough of the Apple iPod, investors are foaming over companies having anything to do with the digital music player. It’s the iPod economy. Apple’s stock is up 187 percent in 2004, and stock in PortalPlayer, the company making some iPod innards, was on fire after going public last month. Synaptics, which makes the iPod’s trademark control wheel, is sporting a 152 percent gain this year.