I have some Fiberology PA12+CF15 blend (link) from a long time ago and recently got around to using it. I am amazed to say the least! It prints easier than PETG, even without an enclosure. Only downside is that it is much more expensive per kg, although it is lower density so I don’t seem to be going through it as quickly as other filaments.
I recently purchased some PC Blend with CF from Prusa as well. I haven’t gotten to print it yet, but I’ve heard very good things about it, too.
What less common filaments do you fine folks like using?
ABS is really good if you can manage the warping reasonably well (enclosure, PEI sheet, >90°C bed temps, suitable part geometry).
But the strength and stability at higher temperatures makes it worth the effort, especially for automotive applications. ASA is even UV stable, making it the perfect outdoor material.