Herpy, it's difficult to tell from your image but it looks more like a wiggle with some fading than a drift.
What setiData file is this from? Lagrange-4?
its from 2010-11-05-HD172175-1420_1
Here are some more from the same data set that seem like they drift and one that looks like it pulses.
If it was drift could you figure out how fast the object was moving?
I tried using wolfram alpha and it said 0.96 c so I am pretty sure I messed that up.
And what are some things that make a signal more interesting. I thought drift was the main thing.
There are a lot of signals in that 2010-11-05-HD172175-1420_1-8bit-01.dat file. It's all the sort of stuff that has been seen many times here http://baudline.blogspot.com/search/label/SETI
I'm downloading the other 12 GB of the HD172175 data series to see how the signals continue. In the setiData page I've noticed that there are 10 different target sets from the 2010-11-05 date. These other files can be used as a post ON-beam / OFF-beam confirmation test. So the next step would be to download each of those data sets and see which of the HD172175 signals persist.
Unfortunately it is not possible to determine how fast the object was moving (if in fact it was an object and not RFI). Doppler drift is caused by acceleration, not velocity.
There are many that seem to persist. So that means it is probably not anything interesting right? I tried to make a picture. That one slanty one seems like it moved over 1000 hz between collections. The straight one stayed in the same place. I haven't gone through all of them so they might be in others too.