Saleae Logic Probe on sale at microchip.com

[ScaleRobotics]

A lot of things the Logic probe can handle. But analog is not one of them. So if it is an analog signal you want to look at, or changing voltage, then you need a scope. For all digital pulses up to 5.5v (I think that is the limit) the probe works very well. So I think you want your scope in your man cave too.

Edit:

Good point Bert, about the not real time. You can set the logic probe to trigger on different inputs, but you basically press start, and then it gets its samples. After it is finished sampling, it displays them for you.

My scope is definitely collecting more dust since I bought the Saleae logic probe.