Planning a feature wall and looking for ideas

Creating a feature wall can genuinely transform a room, adding depth and personality that paint alone often can't achieve. I've been thinking about adding one to my living room, maybe with a bold pattern or a mural. I'm looking for inspiration and advice on what types of wallcoverings work best for different spaces, and whether it's better to go for a textured finish or a smooth one. What themes or styles have people found most effective for their own feature walls?