The Dumbbell Nebula...I guess it looks like a dumbbell?  Some nebula are nurseries for the beginning of a star's life, but this nebula is formed in a star's finale. 
Once a small or medium-sized star has smashed all its hydrogen into helium, the core contracts and becomes much, much hotter. This enormous kiln begins to fuse helium into carbon and oxygen — the building blocks of life. The high temps also create a "stellar wind" that dramatically expands the star's surface, blowing these new elements into space. We calls these "planetary nebula," although it doesn't really have anything to do with planets.

This was more Photoshop-heavy than most of my images, relying on a bunch of masks to get the composition the way I wanted.

Preprocessing
1. Subframe Selector to find and remove subframes with eccentricity ≥ 0.7
2. WeightedBatchProcessing
3. Create preview to crop
4. DrizzleIntegration with Region of Interest to crop to preview (PixInsight crashed halfway through my drizzles, so I lost my crop region, and needed to later StarAlign the images)
5. Dynamic Background Extraction
6. NoiseXTerminator

RGB
7. LinearFit R & B to G
8. ChannelCombination to create RGB
9. ImageSolver script
10. Photometric Channel Combination
11. Histogram Transformation to stretch just a little bit, until the stars are visible but still small
12. StarXTerminator to create star and a starless images
13. stars: CurvesTransformation to saturate image
14. stars: duplicate and Histogram Transformation to make some bigger stars for later

L / Starless
14. L: StarXTerminator to discard stars
15. L: ArcSinhStretch
16. L: Local Histogram Equalization, just a touch, to emphasize interior details (this took a lot of trial and error to get an object that looked natural to me)
17. LRGBCombination to apply L to the starless RGB nebula
18. Curves Transformation to play with color a little

Combination
19. PixelMath to multiply the RGB starless and RGB (small) stars together
20. Export this, and the big stars, to 16-bit TIFFs
21. In Photoshop, layer the small stars (with nebula) on the big stars
22. I created a layer mask on the nebula (small stars) layer, to reveal a handful of big stars below
23. I noticed that the upper layer background was brighter than the lower layer, so I created a layer filter to dim the background of the upper layer, again using layer masks to avoid darkening the nebula and the bottom layer 
24. Applied both curves and levels to the nebula, using a layer mask
25. Finally I noticed that the nebula’s interior stars had been blocked somehow, so I added another star layer on top of everything, set layer mode to “screen”, and made pinholes in the layer mask to add back the stars