Got some midi drum from my e-set and I have a lot of "ghost notes" with a velocity below 25 I'd like to get rid of.
 
Any thoughts?

I'm sure a CAL script could do this but it might be easier to just use Edit Select By Filter.  Like this:
 
Open the event list on the track (I think you can do it in the Piano Roll too but I found it confusing to see if what I wanted was selected there).
Ctrl-A to select everything (or Edit->Select All)
Then Edit->Select By Filter
In the dialog that comes up uncheck everything except Notes and in the Velocity part of Notes put the range you want to select, so say 0 to 25.  Hit OK.
Now only the low velocity notes should be selected, then do Edit->Delete
 

Cool! Never knew this. Should work for duration too, eh?

Yep, the selection rules can include duration.  So you could find super short notes that were keyboard mistakes. 
 
It is the most confusing dialog in SONAR, but it does have a bunch of very powerful features.

There is a cal script for guitar players that tries to remove accidental midi notes.