I’ve got a few questions about this topic. What is this squiggly trace on this pcb, whats it for, and how could I create something like this on Eagle PCB?
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It’s to equalise track lengths for high-speed signals, it’s called serpentine routing. Those tracks look like a differential pair, which need to be the same length.
The Pulsonix software I use will do it automatically for me, calculating the track length, within preset limits. I don’t know if Eagle can do it.
Do you happen to know if Orcad can do it?
I’m not certain, but I’m quite sure that all the pro packages have it.
Awesome, thanks a lot for the info, I hope to use this in future projects. 
Nope… Eagle doesn’t automate that for you. There’s an ULP that calculates trace length (length.ulp / length-freq-ri.ulp), so you could manually do it if there isn’t an ULP that does it for you (I don’t recall seeing one). I would guess that an ULP could be made to introduce serpentine on an existing trace to match another one, as well - it’s within the realm of the code’s possibilities at least.
Once trace lengths start mattering in terms of timing issues, though, I’d say you need to look at the upper-level packages.
ah ok, thanks.
If you did want to do it manually, the ‘Bend a line’ tool (command SPLIT) is the easiest to use, just set up a fine alternate grid and hold the Alt key while ‘bending’ the line, clicking around to make that serpentine pattern. For just a few traces, it’s not so bad.
In most cases, equalizing lengths like that is going overboard. In the example given, there would probably be a fraction of a millimeter difference in track lengths if they didn’t do the “squiggly” equalization. You’d need to be operating at much more than a GHz for this to be a problem.
If your CAD package makes it easy to do, there isn't any particular reason NOT to do it either.In most cases, equalizing lengths like that is going overboard.