I’m currently editing a few sector maps for the next issue, and I wanted to use a new symbol – a hollow triangle – to encircle a star. (Hollow circles, of course, are used for Amber, Red, and Blue Zones).
After fooling around, I found a nifty add on for the free Paint.net editor, from BoltBait.It’s useful and free (although I chipped in $5.00 as a donation.)