If you have misgivings about using strong colors in your home, consider this spectrum of bathrooms. Bathrooms can be the perfect place to experiment with color, because they're usually not too big, and you generally don't spend enough time in them to tire of, say, cobalt or goldenrod.
In my own apartment, the tiny bathroom has the only walls painted something other than white or gray (teal).
The examples above show how colorful paint, tile, and wallpaper can liven up any style of bathroom. If the collage in Image 1 is a bit much for you, calm but colorful aqua is a good standby (Images 4 and 10).
Images: 1. Lonny 2. Heath Ceramics for Design*Sponge 3. Elle Decor 4. Contented Sparrow 5. Domino via Southern Inspirations 6. Canadian House and Home via Desire to Inspire 7. Elsie Marley 8. Living Etc. 9. via Terramia 10. Country Living