On Aug 24, 2005, at 12:16 PM, Rodney A.Hoiseth wrote: > I had posted the same question to the MacWizards list and one of > the Wizards made a suggestion that sounds right, but I haven't > followed up on it yet: He suggested it might be the scroll wheel on > my mouse, (even though he had no way of knowing I had a two-button > mouse with a scroll wheel...) The jumping is similar to the > movement produced by the mouse (a Kensington "Mouse in a Box"). That would be my guess. Try a different mouse and see if it goes away. > Somebody has pointed out that the firewall built into OS X is > probably all that's necessary anyway. That would work, but its usually more convenient to just configure the router once rather than set up a software firewall for each individual computer. That way, you don't accidentally forget to configure a new computer, or have to worry about whether any software update might change some settings. SR